Abstract:During the PCB board is loaded into the SMT, it appears the deviations of position and angle. For this problem, an algorithm of location of target fiducial point based on OpenCV was introduced, and Microsoft Visual Studio 2010 was selected as development tools to develop the interface software. Experimental results show that this algorithm has high reliability, it can accurately extract and locate target contour under complex background, and interface software could help to load the localization algorithm, the whole software has a certain practicality.