How many movies have Noriko Ohara and Yoshimasa Iiyama collaborated on?

They have worked on 18 movies together! Their first movie together was Doraemon: The Record of Nobita, Spaceblazer (1981) while their highest rated movie together was Doraemon: The Record of Nobita's Parallel Journey to the West (1988). They have not worked together since Doraemon: Nobita's the Legend of the Sun King (2000). They are most known for their animation films together.