Objective: To explore the diagnosis and prognosis of supraspinatus tendinitis by ultrasound power Doppler and elastography. Methods: A retrospective analysis of 70 healthy subjects (control group) and 72 patients with supraspinatus tendinitis (observation group) selected from May 2018 to October 2020, all underwent ultrasound examination, and analyzed the affected side of the observation group , Ultrasound imaging performance of the contralateral side, start the ultrasonic energy Doppler, elastography mode, compare the shear modulus value, SWV value, blood flow signal classification, elastic ultrasound classification of the two groups of subjects, and analyze each item with ROC curve Predictive value of numerical value for supraspinatus tendinitis and prognosis, and Spearman method is used to analyze the correlation between various parameters and prognosis. Results: The blood flow increase rate, echo disorder rate, internal calcification rate, and echo uneven rate of the affected side of the patient were higher than those of the healthy side (P<0.05). The SWV value, shear modulus value, blood flow signal classification, and elastic ultrasound classification of the observation group were higher than those of the control group (P＜0.05). After ROC curve analysis, the SWV value, shear modulus value, elastic ultrasound classification, and blood flow signal The AUC of grade and four combined early prediction of supraspinatus tendinitis were 0.932, 0.917, 0.905, 0.921, 0.996, respectively. At the same time, the blood flow signal classification, elastic ultrasound classification, shear modulus value, and SWV value of the good prognosis group are lower than those of the poor prognosis group (P<0.05). After ROC curve analysis, SWV value, shear modulus value, elastic ultrasound The AUC of classification, blood flow signal classification and the four combined early prediction of prognosis were 0.881, 0.922, 0.914, 0.914, 0.995, respectively. After analysis by Spearman method, the prognosis was related to SWV value, shear modulus value, blood flow signal classification, The grading of elastic ultrasound was positively correlated. Conclusion: Ultrasound power Doppler combined with elastography can predict the occurrence, development and prognosis of supraspinatus tendinitis.