Yasuo Ootsuka was a Japanese animator who spent most of his career at Toei Animation and later collaborated with Studio Ghibli.

Ootsuka's obsession with detail started young—he began drawing as a kid after watching trains carry soldiers away during wartime, and that fascination with machinery never left him. It shows up everywhere in his animation work. Before getting into anime, he worked in the statistics department at the Yamaguchi prefectural office, but kept submitting satirical comics to the local newspaper. A couple of business trips to Tokyo convinced him he wanted to be a political cartoonist, so he made the move.

In 1956, he saw a newspaper announcement that Toei was making an anime film called Hakujaden. He went straight to Nihon Douga (the company that became Toei Animation), took the entrance exam, and passed. The examiners included heavy hitters like Yasuji Mori. Ootsuka became one of Toei's first employees and was part of the group experimenting with frame-rate modulation—basically animating important scenes in full detail while roughing out less crucial moments. This technique became what's now called the "money shot" style. He started as temporary staff, which meant half the pay and grinding overtime just to survive, but he eventually secured regular employment.

More importantly, Ootsuka mentored both Hayao Miyazaki and Isao Takahata early in their careers and worked alongside them on several projects. Directors approached him multiple times, but he always declined. He'd watched Takahata struggle directing Hols: Prince of the Sun and came away convinced he didn't have the same directorial chops, despite his deep respect for Takahata's abilities.

Later in life, Ootsuka ran an animation school in Japan. Studio Ghibli eventually made a documentary about him.