Background and Objective: Virgin Olive oil contains Oleocanthal as an anti-inflammatory agent. The main purpose of this study was to compare the effects of ultrasound therapy and phonophoresis with virgin olive oil on female athletes' chronic Low Back Pain (LBP). Materials and Methods: Thirty female athletes with chronic LBP voluntarily participated in this pilot study. Patients were randomly assigned to Phonophoresis (n=15) and Ultrasound (n=15) groups and were treated with virgin olive oil or ultrasound gel for 10 sessions. Frequency and duration of treatment by ultrasound were 1 MHz and 10-min, respectively. Subjects completed Mc Gill, Modified Oswestry and Ronald-Morris standard questionnaires before and after 10 sessions of physiotherapy. Results: There was a significant reduction in symptoms of LBP based on Mc Gill, Ronald-Morris, and Modified Oswestry questionnaires at the end of the therapy in both groups compared to pre-treatment status (P<0.05). 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