The biochemical changes in liver marker enzymes and protein metabolism after repeated exposure to diagnostic ultrasonic waves in rabbits. Thirty-five male rabbits were used for the study; animals were classified to five equal groups. Group I (control group) not exposed to ultrasound (control group) while other groups (II, III, IV and V) were exposed to diagnostic ultrasound (5.5 MHz) 2 times per week for different time (15, 30, 45 and 60min) for 5 weeks, respectively. Our results revealed that a highly significant increase of serum liver marker enzymes (ALT, AST, GGT, Alp activities, total protein), protein concentration in liver tissue, and changes in protein electrophoresis were observed after ten times of ultrasound exposure. Also a significant increase of serum urea and uric acid concentrations were observed in groups III, IV and V. with changes in electrophoretic pattern of liver protein electrophoresis after five and ten times of exposure to ultrasound. Our results showed that, ultrasound exposure had positive anabolic effect on protein metabolism when used for short period as 15 min. However, it had a negative effect on protein metabolism when used for long durations more than 15 min of exposure.