Background: The advantages of USG include low cost, accessibility, and capability for real-time high-resolution imaging that enables a dynamic assessment. Dynamic examination of shoulder can be carried out in multiple planes and areas of concern can be focused promptly to make a diagnosis. The aim of this study was to evaluate the role of ultrasound in diagnosis of common shoulder joint lesions. Methods: Our cross sectional study was carried on 36 patients who were referred from outpatient clinics to the radiology department with shoulder complain, the first assessment done by US and finally confirmed by MRI as a gold standard. Results: US predicted patients with SSP tendinopathy, with accuracy, sensitivity, specificity, PPV and NPV was 55.6%,100%, 72.7%, 70% and 100% respectively (p < 0.001). US was able to predict patients with SSP partial tear, with accuracy, sensitivity, specificity, PPV and NPV was 88.9%,80%, 100%, 100% and 80% respectively (p < 0.001). US was able to predict patients with SSP full thickness tear, with accuracy, sensitivity, specificity, PPV and NPV was 100%,100%, 100%, 100% and 100% respectively (p < 0.001). US was able to predict patients with Biceps long head tenosynovitis with accuracy, sensitivity, specificity, PPV and NPV was 94.4%,100%, 91.7%, 85.7% and 100% respectively (p < 0.001). Conclusion: USG can be used as an initial line of investigation for evaluation of all patients who are clinically suspected to have rotator cuff disorders which are the most common cause of shoulder pain.