The invention discloses a curved surface defect automatic detection method and an apparatus thereof. The method comprises the following steps: 1, at a
training phase, acquiring sample images, constructing a
training set, performing manual defect identification on images in the
training set, and marking areas where all defects appear; for each image in the
training set, executing a defect pre-positioning step so as to obtain areas R where all the defects may appear; comparing the R with the manually marked areas where all the defects appear, and according to an overlap degree of the two, obtaining negative samples and positive samples through division; according to the positive samples and the negative samples, performing offline training of a deep neural
network model, and outputting types of defect areas and concrete coordinates; and 2, at an online detection phase, acquiring current curved surface images to be detected, executing a defect pre-positioning step, obtaining sets R, and inputting the R into the
network model, and obtaining the types and the concrete coordinates of the defect areas. The method and apparatus have the advantages of high adaptability, high real-time performance and high identification accuracy.