The invention discloses a mobile phone glass cover plate window area defect detection method based on machine vision. The method comprises the following steps of 1, acquiring a mobile phone screen image; 2, carrying out rough detection on a mobile phone screen area; 3, extracting defects of the mobile phone screen image through a threshold segmentation algorithm; 4, connecting the scattered pointsin the dense point cluster area by using a clustering algorithm; 5, performing defect classification by using a neural network classifier; 6, extracting the area, the length and the radius of the defect area, and comparing according to a detection standard; 7, re-classifying the defects by using a deep learning classifier; and 8, counting information and quantity of various defects. According tothe detection algorithm, the principle of rough detection and fine detection in sequence is followed, the defects of pits, scratches, dirt, broken filaments and the like in the screen areas of the mobile phone glass cover plates of various different types can be rapidly and accurately extracted, and meanwhile the detection precision can be adjusted according to the detection standards of differentproduct window areas.