A sheet conveyance mechanism in the present disclosure has a feeding portion, a pair of registration rollers, a first sensor, a second sensor, and a conveyance control portion. The feeding portion has a drive roller. The registration rollers are disposed in a downstream side of the feeding portion. The first and second sensors detect presence of a sheet. If after a sheet is detected by the first sensor, the sheet is not detected by the second sensor by a time when a first period elapses, the conveyance control portion starts a slowdown of a rotation speed of the drive roller. If the sheet is detected by the second sensor by a time when a second period elapses after the slowdown of the rotation speed of the drive roller starts, the conveyance control portion returns the rotation speed of the drive roller to a rotation speed before the slowdown.