〔Abstract〕 Objective To investigatethe correlation between the entrance morphology of the bicipital groove morphology and biceps tendinitis and to analyze the related factors. Methods A total of 80 cases of people with biceps tendinitis and 80 cases of healthy subjectswere included in this study. The the AW4.6 workstation of PACS system and the Functool software were used to measure the morphological index of cases on axial MRI pictures. Results There was significant difference between opening angle(OA) and the ratio of the depth and width of bicipital groove(R1)(P<0.05) in two groups.However, there was no significant difference(P>0.05) was found on the width of bicipital groove(BGW), depth of bicipital groove(BGD), diameter of biceps tendon(BTD), diameter of humeral head(HHD), medial wall angle(MWA), and the ratio of the depth of bicipital groove and humeral head medial diameter(R2). There was a statistically significant difference in the classification of the entrance between the two groups., while there was no statistical difference between the normal shape of the entrance.In the analysis of related factors,there was a statistical difference in tendon diameter between degree 1 and degree 2 of the biceps tendon.However,there was no statistical difference in the MRI measurements of the intertubercular sulcus according to the classification of the complications of biceps tendon injury and the degree of injury. Conclusion There are a bigger OA and a smaller R1 in people with biceps tendinitis. A shallow groove is a predisposing factor for biceps tendinitis,and the greater the degree of injury of biceps tendon, the smaller the diameter of tendon.