Top 10 Cartoon Episodes with the Saddest Endings

This list will focus more on the sadness of the endings of cartoon episodes rather than the episodes as a whole.

These are the endings from cartoon series that, instead of providing a traditional happy ending, end up leaving the audience in tears.

The Top Ten

I Remember You - Adventure Time

Marceline and the Ice King share a song that reveals his forgotten past and their emotional history. His mental deterioration contrasts with her memories of who he once was.
You're Getting Old - South Park

Stan begins to perceive the world as unpleasant noise, causing a rift between him and his friends. His parents separate, and he finds himself alienated from his former life.

By far the saddest ending for a South Park episode, made even sadder by the song "Landslide" playing. We get a montage of Randy and Sharon splitting up, and Stan and Shelly moving away. Meanwhile, a friendship forms between Kyle and Cartman, while Stan is left completely alienated from all his friends as the episode ends.
Mother Simpson - The Simpsons

Homer reunites with his mother after believing her dead for decades. She is forced to flee again, and he is left sitting silently on his car.

After finally reuniting with his mother and learning why she had to leave, their reunion is cut short when Mr. Burns shows up at the Simpsons' house to arrest her. However, Chief Wiggum tips Homer off, and he is forced to say goodbye to his mother, not knowing if they will ever see each other again.
The Luck of the Fryrish - Futurama

Fry believes his brother stole his name and dream but learns his nephew was named in his honor. He discovers the statue was a tribute, not theft.

The ending was so emotional. Fry attempts to retrieve his lucky clover, then discovers that the Philip J. Fry he thought was his brother Yancy, who took his name and dreams, was actually his nephew. Yancy had named his newborn son Philip J. Fry in memory of Fry following his disappearance. The episode ends with Fry leaving the clover at his nephew's grave as the song "Don't You (Forget About Me)" plays in the background.
Bye Bye Butterfree - Pokémon

Ash releases his Butterfree so it can be with its mate. He watches it fly away, recalling their time together.

Ash is forced to say goodbye to the very first Pokémon he ever caught so it could start a family of its own.
Jurassic Bark - Futurama

Fry finds the fossilized remains of his dog Seymour and considers cloning him. He ultimately declines, unaware Seymour waited for him until his death.

Just the scene of Seymour continuing to wait for Fry until he became fossilized made the episode all the sadder.

The rest of the list can't even touch "Jurassic Bark" as the saddest episode ever. If you don't cry over the final two minutes, you don't have a heart.

I'm bawling just thinking about this episode.
Baby Doll - Batman: The Animated Series

An actress with a childlike appearance has a breakdown over her lost fame and normal life. She emotionally confronts her inability to grow up.

It's a really sad and tragic episode featuring the main villain, Mary Louise Dahl, aka Baby Doll. She was diagnosed with a condition that kept her from growing, making her look like a little girl for the rest of her life. A former child star, she tried to break into acting after her show was canceled, but her career tanked. She eventually kidnaps all the actors from her show so she can have "her family" back, as it was the only time she ever felt any real happiness.
At the end of the episode, while escaping from Batman, she ends up at a funhouse. She comes across a hall of mirrors and sees one mirror showing how she believes she should look without her condition. She goes berserk, blasting all the mirrors until she runs out of ammo, leaving only one mirror: the one with a reflection of herself as her older self. She then breaks down in tears before surrendering.
The Crossroads of Destiny - Avatar: The Last Airbender

Zuko chooses to side with Azula, betraying Iroh and Aang's group. Aang is critically injured, and the team barely escapes.

This episode, along with the previous one, The Guru, plays out like the ending of Star Wars: The Empire Strikes Back. Aang abandons his training with the guru after getting visions of Katara in danger back in Ba Sing Se. In the final moments of the episode, Azula manipulates Zuko into aiding her, along with the Dai Li agents. Aang is forced to enter the Avatar State, meaning he would have to let go of his attachment to Katara. But just as he is about to do so, Azula shoots him in the back with lightning, causing him to fall and severing his ties with his past lives. Katara manages to save him, and they are rescued by Iroh, who holds off the others so she and Aang can escape.
Come Along with Me - Adventure Time

The series finale weaves a future storyline with the final battle against GOLB. It ends with a musical montage and a vision of peace.

If you want to get into this cartoon, please watch only the first six seasons. The miniseries Mis-Takes turned it into Mis-Adventure Time. A Marceline with a heartbeat isn't the Marceline I knew and fell in love with.
Rose's Scabbard - Steven Universe

Pearl shows Steven the hidden complexities of her past with Rose Quartz. Her sense of purpose is shaken when Steven uncovers Rose's secrets.

I thought this was the saddest episode so far.

The Newcomers

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Neon Express - Astro Boy (2003)

A sentient train grapples with its obsolescence and eventual decommissioning. Astro helps it find peace before its shutdown.
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Things Change - Teen Titans

The Contenders

Blue Cat Blues - Tom and Jerry

Tom sits on railroad tracks after losing his love to a rich rival. Jerry joins him, having faced heartbreak of his own.

This is probably one of the saddest endings for a cartoon: Tom sits on the railroad tracks as Jerry explains what caused Tom's death wish. After Jerry gets sacked by his lady friend, he joins Tom on the railroad tracks, and train whistles are heard as the cartoon fades to black. What's probably sadder is that Tom doesn't fight Jerry when he joins him. He just moves aside to make room for Jerry to sit with him.

I don't know if it was sad, but it definitely was very dark.

I'm so glad I never watched that episode as a kid.
Gang Wars - Fat Albert and the Cosby Kids

Fat Albert and the gang attempt to mediate a conflict between rival neighborhood groups, but tensions quickly escalate into violence. The confrontation results in a young boy named Danny being shot and killed, marking a grim departure from the show's usual tone. The episode ends with the characters mourning at Danny's funeral, delivering a stark message about the real-world consequences of gang warfare.

After Fernando is killed while trying to save his brother and prevent a gang war, Fat Albert and the gang unveil a new park the next day. They name it after Fernando in honor of his memory. Fat Albert delivers a heartfelt speech that Fernando was supposed to give. In the speech, he mentions how Fernando joked that he wouldn't forget them when he became famous. Now, they won't forget about him and his courage in trying to stop a gang war.
Meanwhile - Futurama

Fry and Leela live an entire lifetime together after time freezes. The Professor eventually offers to reset time, erasing their shared years.
Dipper and Mabel vs. the Future - Gravity Falls

Great Uncle Ford offers Dipper an apprenticeship to stay in Gravity Falls and study anomalies, a proposal he initially accepts with enthusiasm. However, Mabel inadvertently overhears the conversation and feels betrayed by the prospect of being separated from her twin brother. She runs into the woods in distress, where she is manipulated by Blendin Blandin, setting the stage for the chaotic series finale.
Aftershock - Teen Titans

Terra eventually breaks free from Slade's control and turns her powers against him to stop a massive volcanic eruption. Realizing she cannot save the city without sacrificing herself, she pushes her abilities to the limit and is turned into a stone statue. The Titans arrive too late to save her, leaving them to mourn their friend at the site of her final, heroic act.
The Titanium Ninja - LEGO Ninjago: Masters of Spinjitzu

Zane sacrifices himself to defeat the Golden Master and save Ninjago. His friends mourn his apparent death as the episode closes.

Zane sacrifices himself to destroy the digital Overlord, perishing in the process. He is then honored by the entire city for his sacrifice, and the episode ends with a tinge of hope that he may still be alive.
Starcrushed - Star vs. the Forces of Evil

Star confesses her feelings to Marco before returning to Mewni. The revelation strains their friendship just as a new threat emerges.
Kenny Dies - South Park

Kenny becomes terminally ill and eventually passes away. The boys struggle with the concept of death, and Stan avoids visiting him.

It was hard to see Kenny go because he was my favorite character, and he had died so many times before.
A Regular Epic Final Battle - Regular Show

Mordecai, Rigby, and friends engage in a final showdown to save the universe. After their victory, life moves on and they go their separate ways.
Tales of Ba Sing Se - Avatar: The Last Airbender

This anthology episode presents several short vignettes that explore the daily lives of different characters within the Earth Kingdom capital. While some segments are comedic, the story focuses on Iroh as he prepares a memorial for his deceased son, Lu Ten. The segment concludes with Iroh tearfully singing Leaves from the Vine, delivering one of the most heartbreaking moments in the series.

Iroh celebrates the birthday of his dead son. It is very sad.
Homecoming - American Dragon: Jake Long

Jake tries to bring Rose back to his world after her memory is wiped. She chooses to stay in her new life, and he lets her go.

A very touching ending. Jake meets up with Rose after wishing that she had never been taken by the Huntsclan, which, of course, erases any memory she ever had of him. Their meeting is brief, as Rose tells him that she is moving to Hong Kong with her parents, meaning that she and Jake won't be able to see each other anymore.
Operation: I.N.T.E.R.V.I.E.W.S. - Codename: Kids Next Door

The KND members are evaluated for their future in the organization. Numbuh One chooses to leave Earth to continue his mission in space.

Numbuh 1 is forced to say goodbye to his family and friends.

Farewell, Numbuh 1, until we meet again.

This episode made me cry at the end.
The Bot - Wander Over Yonder

The Bot is sent on a mission to destroy a planet but ends up questioning its purpose. Its final act is a self-sacrifice to prevent destruction.
The Library - Avatar: The Last Airbender

Team Avatar explores a hidden spirit library in search of strategic information. The library begins to sink, and they barely escape with tragic consequences.

Appa is taken away by sandbenders. The episode ends with Aang shedding a tear due to the loss of his bison.
Pony Puppy - My Little Pony (1987)

The ponies try to care for a baby puppy that becomes too large to handle. In the end, they let it go to live safely elsewhere.