The invention discloses a control system and method for knitting missed stitches of a flat knitting machine on the basis of machine vision. The system comprises a flat knitting machine master control board, a flat knitting machine head controller, a motor position encoder, a camera, an assisting drive mechanism, a communication module, and a vision operating module. The flat knitting machine master control board, the flat knitting machine head controller and the motor position encoder are connected in parallel and communicated through a CAN bus. The vision operating module is connected with the assisting drive mechanism. The camera is connected with the vision operating module. The vision operating module is connected and communicated with the communication module. The communication module is connected and communicated with the flat knitting machine master control board through a CAN bus. The system runs stably and reliably. Through a real-time vision detection method, missed stitch defects during knitting of a flat knitting machine head can be detected in an automatic manner.