Outcomes of traditional treatment methods of lateral epicondylitis are variable because of poor tendon healing properties secondary to poor vascularization. Platelet rich plasma provides locally high concentration of growth factors and have shown its efficacy in many tendinopathies and wound healing. We tried to measure the efficacy of locally injected autologous PRP, subjectively by functional oxford elbow score and pain score as well as objectively by ultrasonographic evaluation of the morphologic changes (focal hypoechoic, odema, tendon thickness, fraying, tear, cortical erosion, calcification) in common extensor origin in 30 patients with mean age of 39.3 years of recalcitrant lateral epicondylitis. The mean pain VAS Score improved from 7.7 before injection to 1.8 at final follow up i.e. after 6 months post injection. The Oxford elbow score improved from a mean of 19.2 prior to treatment to 41.3 after the injection at final follow. Ultrasonography of the involved elbow showed decrease in focal hypoechoic, decreased edema, improvement in thickness of the tendon and healing of the tear at the origin site. This study confirms that local PRP by supplying growth factors helps to enhance the stromal and mesenchymal stem cell proliferation and increases tendon vascularity and prevents angiofibroblastic degeneration and thus improves tendon repair and healing property by releasing growth factors and increasing vascularity, which can be documented by improved tendon morphology.