To resolve the problem of quality detection in the manufacturing process of smart card, an on-line visual inspection scheme based on SIM is proposed.We present a localization algorithm based on geometric feature matching combining the lighting scheme and algorithm design.It is implemented through the design of image's light source collection and research of the positioning and detection algorithm of module.Some key technologies, such as edge detection, feature extraction, opening and closing operation and object recognition are used in this algorithm too.It is useful for detecting if there is the chips, and other problems like dirts, rusts, banding severe bending fracture, decorative pattern, crease, silica gel on the back of migration, silica gel thick, scrapped modules silicone abnormal bulge, module stripe location hole on the back of damage, et al.Test results show that the system is an effective implementation of the quality detection of SIM card.