Objectives: To compare the effectiveness of short wave diathermy (SWD) and high velocity low amplitude thrust manipulation (HVLATM) for management of chronic mechanical low back pain on outcome measures like VAS, ODI, ROM (flexion, extension). Materials and Methods: Study Design: Experimental study. A convenient sample of 30 patients was taken. They were assessed by the orthopedecian for mechanical low back pain. After obtaining their consent, routine assessment was done and outcome measures were obtained on VAS, ODI and ROM (flexion, extension by using Modified Schobers method). Pre and post treatment (9th session of the treatment), outcome measures were assessed. Results: Total 30 subjects, 15 in HVLAT group AND 15 in SWD group were conveniently allocated. There was significant difference on above outcome measures between the two groups (p=0.000). In comparison with SWD (group 1) and HVLAT (group 2) showed more significant improvement on VAS, ODI and ROM in chronic mechanical low back pain subjects. Conclusion: We conclude that high velocity low amplitude thrust manipulation can be used in rehabilitation of chronic mechanical low back pain patients.