Pixar president Jim Morris and Walt Disney Animation Studios president Andrew Millstein will continue in his place, as the 73-year-old transitions to an advisory role to end in July 2019.

Morris and Millstein will report up to Walt Disney Studios President Alan Bergman and the Pixar-Walt Disney Animation Studios Chief Creative Officers Pete Docter and Jennifer Lee. All roads lead to Walt Disney Studios Chairman Alan Horn.

"Never in my wildest imagination could I have conceived of the path or the extraordinary people I have worked with over all of these years - the twists and turns, the ups and downs, along with exhilarating passion, talent, and dedication that have led to something extraordinary, something that has an enduring impact in the world," Catmull said in a statement.

Catmull's pioneering work in computer animation and visionary leadership in key technology companies including Lucasfilm, Pixar, and Disney over the past 45-plus years changed the face of film.

Catmull was hired by George Lucas in 1979 to lead Lucasfilm's computer division, before co-founding Pixar Animation Studios in 1986 with Steve Jobs and John Lasseter.

Pixar released the world's first feature-length computer animated film, the seminal "Toy Story," in 1995 and has broken creative and technological boundaries ever since.

The studio's 20 feature films have won 15 Academy Awards and earned more than $US13 billion in global box office; its most recent film, "Incredibles 2," broke records in its debut and is the highest grossing animated film in US box office history.

Australian Associated Press