Objective: to compare the effects of high intensity laser versus low intensity laser in treating patients with lateral epicondylitis (LE). Methods: forty participants in this randomized, single-blinded, repeated measurement study with lateral epicondylitis, their age ranged from 30 to 50. Participants were classified into two groups at random, group (A) (n = 20), which received high intensity laser therapy (HILT) and strengthing exercise, group (B) (n = 20), which received low intensity laser therapy (LILT) and strengthing exercise. Visual analog scale, hand dynamometer and disabilities of the arm, shoulder and hand questionnaire were utilized to measure pain intensity, hand grip strength and functional disability respectively, before treatment, 2 weeks and 4 weeks after treatment. Results: there was a significant improvement (p < 0.05) in pain intensity, hand grip strength and functional disability in both groups after 2 weeks and after 4 weeks of treatment. Conclusion: In conclusion, pain severity, hand grip strength, and function abilities were all enhanced with the use of both HILT and LILT in patients with LE. In contrast to LILT, the treatment impact of HILT on LE is both more rapid and more significant in less number of treatment sessions.