Highly integrated on glue gun, Glue Bead Inspection system detects coating quality inline and gives warning on defect through real-time image acquisition and intelligent algorithm. It inspects the width, position and continuity of block glue, without occupying too much working time and is compatible with many models to provide high-performance and flexible visual inspection tools for coating quality monitoring. According to the characteristics of different processes, optical sources of different wavelengths are adopted to cope with the difference in plate material and glue color, and special optical processing methods are used to solve the problems such as large angle of glue gun, similar colors of panels and glues. The system is designed with concise and efficient man-machine operation interface to facilitate manual view and information exchange. Relevant defect information can be saved and marked in the system for the purpose of backward retrospect of vehicle quality analysis and closed-loop improvement.