A 3-D vision sensor and a visual inspection system for welded beads of automotive panels using this sensor have been developed. The items to be inspected are the depth, width, flushness, and inclination angle of the welded point. The 3-D vision sensor detects the section line of the welded bead using slit light method in real time, and the inspection system calculates the four inspection items from the section line. The measurement accuracy levels of this system are ±0.02mm for the depth and flushness, ±0.01mm for the width, and ±7 deg. for the inclination angle. Moreover, the system is able to inspect a single welded bead in 150ms. This system has been used particularly in an automotive factory.