It has had two anime adaptations, both by Toei Animation.
- Moretsu Ataro (1969-1970), which was one of the last anime to be broadcast in black and white. It switched to color toward the end of its run.
- Moretsu Ataro (1990), which was the series to introduce Momoko, a replacement for Totoko, a similar Akatsuka girl licensed out to Pierrot around the same time.
Moretsu Ataro shows examples of:
- Cats Are Mean: Nyarome, to an extent. He is shown to steal vegetables and be an all-around jerk sometimes.
- Crossover: Episode 74 of the 1969 series prominently feature characters from Osomatsu-kun, plus Papa in Tensai Bakabon (his first animated appearance before his own show in 1971).
- A non-Akatsuka crossover happened in the final episode of the 1969-70 anime, where Kokoro no Boss is seen talking to Zeni Geba, a manga character created by George Akiyama that ran in the same magazine as Ataro, Shonen Sunday.
- Deceased Parents Are the Best - X-Goro, Ataro's wise ghost dad.
- Funny Animals: Kokoro no Boss and all his raccoon lackeys.
- Mascot with Attitude: Admit it, a talking, trouble making, womanizing cat is as marketable as you can get.
- Series Mascot: Nyarome, Beshi, and Kemunpasu. Given that they're talking animals in an otherwise serious set up, this was inevitable.
- Spell My Name with an "S": While his name is supposed to be X-Goro, it is sometimes romanized as Batsu-goro, which is how his name is meant to be pronounced.
- Suspiciously Similar Substitute: For the 1990 anime, the Police Officer from the original was replaced by a similar character due to Studio Pierrot having the animation rights to the character at the time.