A sheet conveying device includes a tray, a device body having a conveying route of a sheet and supporting the tray, a side guide supported by the tray to be movable in a first direction intersecting with a conveying direction of the sheet and contacting an end portion in the first direction of the sheet placed on the tray, a cover rotatable with respect to the device body and covering the conveying route, and a lock lever locking the cover to the device body and provided in a position overlapping the side guide in a second direction intersecting with the conveying direction and the first direction. The lock lever is rotatable between a lock position where the cover is locked and a release position where the cover is released. The side guide includes a first notched portion facing a rotation track of the lock lever with a gap.