The invention provides an image segmentation quality evaluating method based on an ROC Graph. The image segmentation quality evaluating method includes the following steps: firstly, dividing pixels in a to-be-evaluated segmentation image into four types by comparing with a reference segmentation image; secondly, leading in pixel space information, performing distance transform on pixels in the reference image, and calculating distance from each pixel to a target boundary; thirdly, giving a weight to a pixel at a corresponding position in the segmentation image according to distance coefficient of each pixel in the reference image; fourthly, utilizing the weights to calculate a weighted true positive rate wTPR and a weighted false positive rate wFPR, and depicting a point (wFPR, wTPR) in the ROC Graph; fifthly, according to distance from the point (wFPR, wTPR) to a point (0,1), scoring the segmentation image, wherein the higher the score is, the better the segmentation effect of the to-be-evaluated image is. By the image segmentation quality evaluating method, quality of the segmentation image can be evaluated effectively, and the evaluation result is more reasonable and more visual and consistent with subjective evaluation result of human vision.