Objective To investigate the application effect of the improved "L" type Limb support frame in the "Looking at the moon" position during endoscopic breast cancer surgery. Methods According to the admission successively, 76 patients were divided into the control group and the observation group with 38 patients in each group. The traditional "Looking at the moon" position was adopted by the control group and the "Looking at the moon" position was adopted by the observation group with the modified "L" shape Limb support frame. Results There were statistically significant differences in operation time, position indexes and postoperative comfort level between the two groups of patients (P<0.05 for all). Conclusion The improved "L" type Limb support frame can improve the efficiency of surgical posture, improve the safety and comfort of patients, and reduce the complications related to surgical posture.