The aim of this study was to assess the effect of low level laser therapy (LLLT) on bone turnover markers in ovariectomized rats. Thirty adult female albino rats were used in this study and divided into three groups: Group (1); 10 sham-operated rats served as controls group (2); 10 bilateral ovariectomized rats (OVX), and group (3); 10 OVX rats exposed to LLLT. LLLT was applied on the neck and shaft of femur, 5 times/week for 8 weeks. The dose applied on each point was 1000 Hertz, 5 Watts for 30 seconds with a total dose of 15 mJoule/cm 2 .At the end of the experiment, blood samples were collected and sera were separated for determination of serum calcium (Ca), inorganic phosphorus (Pi), osteocalcin and alkaline phosphatase (ALP). In addition, a 24 hour urine sample was also collected from each rat for the determination of urinary calcium, phosphorous, and deoxypyridinoline(DPD)/creatinine. Results showed significant increase in serum Ca, Pi, ALP, osteocalcin, and significant decrease in U-DPD/creatinine in LLLT exposed group as compared to the other two groups. Bone morphological results revealed increase in calcium deposition and alkaline phosphatase of femoral bones of LLLT exposed group in comparison to sham-operated and OVX rats. Using software image analysis showed increased osteoblast numbers, decreased osteoclast numbers and increased compact bone thickness in LLLT exposed group. Significant positive correlations were obtained between osteoblast numbers and serum Ca, Pi, ALP, and osteocalcin in LLLT exposed group, while a significant negative correlation was noticed with U-DPD. In conclusion, the use of LLLT was found to be effective in enhancing bone formation, decreasing bone resorption in the osteoporotic OVX rats. Further studies are necessary to investigate the effect of different parameters of LLLT as wave length, duration, and also numbers of sessions. The potential use of LLLT in postmenopausal women with osteoporosis is needed to be verified.