Objective To analyze and evaluate the effect of pneumatic therapy instrument in preventing venous thrombosis of lower extremities after gynecological surgery. Methods 98 patients with gynecological surgery admitted in our hospital from January 2015 to January 2016 were selected as the research subjects. They were divided into group A and group B, respectively, 51 cases and 47 cases. Group A was treated with air pressure therapy, and group B was given routine massage therapy, their effect for venous thrombosis were compared. Results The risk of venous thrombosis in group A was 3.92% (2/51) in group A and 23.40% (11/47) in group B, and the difference was significant (P <0.05). The excellent and good rate of prevention and treatment of group B was 84.31%, of which excellent was excellent in 29 cases, good in 14 cases and middle in 7 cases. The excellent rate of prevention and treatment in group B was 59.57%, among which 20 cases were excellent, 9 cases, 10 cases. The difference was significant and statistically significant (P <0.05). Conclusion Gynecological treatment after the treatment of pneumatic therapy instrument can significantly reduce the incidence of venous thrombosis of lower extremities, the prevention effect is ideal, it is worth promoting.