The invention relates to a determination method for quantitatively detecting a thick cabo rate and long and short cabo rates in caboes on the basis of an X-ray transmission image. By utilizing X-ray image feature difference between the caboes and tobacco leaves, the method adopts gray-scale morphological denoising and image segmentation by a region growing method to preprocess an image, meanwhile,a fuzzy C-mean value clustering algorithm based on an unsupervised machine learning function is adopted for belonging judgment, and according to a shape judgment factor, an image recognition algorithm for the nondestructive detection and recognition of caboes in tobacco leaf material are designed and implemented. Moreover, according to a conventional definition standard for thick caboes and longand short thick caboes, a quantitative detection algorithm for cabo morphology is further established, which includes the detection and calculation of the thick cabo rate and the long and short cabo rates, a thick cabo rate detection algorithm mainly relates to cabo diameter extracted by a segmented bounding rectangle method, thickness cabo judgment and thick cabo quality calculation. A long and short cabo rate detection algorithm mainly relates to cabo skeletonization, skeleton length calculation, long and short cabo judgment and quality calculation. The advantage is that the determination method can remarkably increase the accuracy of a detection result and working efficiency and eliminate anthropogenic influence.