Intelligent miniaturized medical devices have attracted more and more attention in the medical industry. These products are mainly composed of some micro electronic components, in which the point line connection structure of the device core chip needs to be completed by high-precision welding. Therefore, the higher recognition accuracy of solder joint and welded core wire is required. Whether they can be accurate and effective identification directly affects the final quality of welding. In order to complete the recognition of solder joint and core wire in the welding process with high quality, this study mainly uses the method of electronic microscope instrument combined with host computer VS17 + OpenCV to complete the image processing, and recognizes the solder joint and core wire end of the collected image. The color and geometric features of solder joint and core wire end are taken as the analysis object. After preprocessing, the region of interest is highlighted through their respective feature analysis. The segmentation process of solder joint and core wire end is completed through specific color threshold selection method and contrast enhancement algorithm. The recognition accuracy error of measured solder joint and core wire end is required within 0.1 mm. The experimental results show that the proposed identification algorithm of printed circuit board (PCB) solder joint and core wire end can effectively identify the position of solder joint and core wire end in the image and display its pixel coordinate value. After data sorting and analysis, the identification accuracy error of this algorithm is controlled within the tolerable range.