A sheet manufacturing apparatus includes a first sieve that has a first opening for screening a defibrated material that is defibrating-processed, a second sieve that has a second opening having a size equal to or greater than a size of the first opening and refines the defibrated material passing through the first sieve by causing the defibrated material to pass through the second opening, and a belt on which the defibrated material passing through the second sieve is deposited.