Provided is a sheet manufacturing apparatus with which the time until the apparatus stops can be shortened. The sheet manufacturing apparatus (100) is provided with: a sieve unit (40, 60) into which at least a portion of a defibrated product that has undergone defibration is introduced and moved at a first speed and in which the defibrated product is passed through multiple openings provided in the main body; and a forming unit (70) for forming sheets using what has passed through the openings of the sieve unit (40, 60). When stopping manufacturing by the sheet manufacturing apparatus (100), the sieve unit (40, 60) is stopped while retaining the introduced defibrated product inside the sieve unit (40, 60).