Objective To explore the evaluation value of blood flow signal score combined with shear wave velocity (SWV) for tendon injury of supraspinatus. Methods A total of 80 patients with tendon injury of supraspinatus confirmed by clinical and imaging examinations in the hospital were enrolled between August 2020 and August 2022. The blood flow signal score was evaluated by power Doppler ultrasound, and SWV was detected by shear wave elastography (SWE). Taking arthroscopy results as the golden standard, the severity of tendon injury was evaluated, and the diagnostic value of blood flow signal score and SWV for tendon injury was evaluated by receiver operating characteristic (ROC) curves. Results Among the 80 patients with tendon injury of supraspinatus, arthroscopy showed that there were 21 cases with chronic wear, 32 cases with partial tear and 27 cases with full-layer tear. The results of ROC curves analysis showed that the sensitivity, specificity and area under the curve (AUC) of blood flow signal score, SWV and combined detection in the diagnosis of tendon tear were (67.80%, 69.49%, 98.31%), (85.71%, 80.95%, 80.95%) and (0.760, 0.735, 0.896), respectively. The sensitivity and AUC of combined detection were significantly higher than those of single index (P<0.05). Conclusion Blood flow signal score combined with SWV can effectively improve the diagnostic sensitivity and efficiency of tendon tear in patients with tendon injury of supraspinatus.