The invention relates to a stitching device and a material alignment stitching method. In the stitching device and the material alignment stitching method, a positioning mechanism is arranged in a loading area of a workbench; thus, when a to-be-stitched material is placed, the to-be-stitched material can be placed on the edge placing position indicated by the positioning mechanism and then is sucked through the wind suction of a wind suction mechanism before other to-be-stitched materials can be put, and the other to-be-stitched materials are aligned with the to-be-stitched material put in advance according to the preset requirements; after that, a pressing seat is driven to move downward by a pressing drive device, so that a driving roller presses the to-be-stitched material; after the wind suction mechanism is closed, a transfer drive device can be started to drive the driving roller to rotate, and the to-be-stitched material is delivered to a stitching station for stitching; and the whole stitching process is simple and convenient to operate, the assistance of other assisting mechanisms is not needed, and the stitching and aligning efficiency is high.