The machine Vision technology and LabVIEW Assistant are used to detect and analyze the glass defects, and the common defects of acrylic glass are mainly scratches and bubbles.The image processing module process on LabVIEW includes the gray level transformation and morphology, threshold value, and the particle analysis is carried out at last. In this study, the defects of glass were identified by template matching. The results show that this method can accurately detect the existence of scratches and bubbles, and judge the location and number of defects. The correct rate is 94% .