Purpose: This study was conducted in order to determine the effect of visual and tactile feedback on muscle activity of the gluteus maximus (Gmax) and abdominal muscles and the motion of pelvic rotation during performance of clam exercise (CE). Methods: Thirteen subjects without low back pain were recruited for this study. Each subject was instructed to perform the CE without and with feedback. The subjects were instructed to keep pelvic from rotating backwards by palpating the ASIS and monitoring the pelvic movement by themselves during performance of CE with feedback. The electromyographic (EMG) activities of Gmax and abdominal muscles were collected using surface EMG. Angles of pelvic rotation were measured using a 3-dimensional motion-analysis system. Paired t-tests were used for comparison of EMG activities in each muscle and the angle of pelvic rotation. Results: The EMG activities of all abdominal muscles were not significant between CM without and CM with feedback (p>0.05). The EMG activity of Gmax was significantly greater in CM with feedback compared with CM without feedback (without vs. with feedback; 14.2% vs. 20.7%MVIC) (p<0.05). The angle of pelvic rotation was significantly less in CM with feedback compared with CM without feedback (without vs. with feedback; $15.3^{circ}$ vs. $10.8^{circ}$ ) (p<0.05). Conclusion: Therefore, these findings suggest that CM with the visual and tactile feedback is effective in activation of the Gmax and correcting of the uncontrolled lumbopelvic rotation during CE.