Background: Low back pain (LBP) is the second cause of pain after headache and remains one of the most comrnon symptoms for see ing a physician. About 90% of LBP is caused by mechanical factor. There are various physical modalities to relieve pain, such as, Short Wave Diathermy (SWD) and Transcutaneus Electrical Nerve Stimulation (TENS) which are proved to be useful to relieve pain. The aim of …