A read image capturing system includes a reading device, a read image capturing circuit, and a signature managing circuit. The reading device reads an image from an original document. The read image capturing circuit captures the read image read by the reading device. The signature managing circuit manages a signature image for causing the read image capturing circuit to capture the read image as a signature capturing image for each user. The read image capturing circuit that captures the read image in association with a user who is associated with the signature capturing image by the signature managing circuit, the signature capturing image having a similarity degree with the signature image included in the read image equal to or more than a similarity degree for capture.