Objective To put forward the problems in applying portable disposable low pressure vacuum drainage system for modified radical mastectomy and to propose the solutions. Methods We retrospectively analyzed the clinical data of 268 breast cancer patients who were treated with portable disposable low pressure vacuum drainage system after receiving modified radical mastectomy in Changhai Hospital from January 2013 to September 2013.Based on the use of ordinary vacuum ball, the patients were divided into dual-chamber group and single-chamber group. The incidence of bleeding at the puncture sites, volume of post-operation drainage, indwelling time of drainage tube, and hospitalization stay were recorded for the two groups. Results A total of 23 cases had puncture site bleeding, including 22 early bleeding and one delayed bleeding. For the dual-chamber group, the indwelling time of parasternal drainage tube was significantly shorter than that of axillary drainage tube median: 5.0 d vs 9.0 d, Z=-10.713, P=0.000). The drainage time (median: 9.0 d vs 10.0 d) and hospitalization stays (median: 9.0 d vs 9.0 d) of the two groups were not significantly different. It was found that 97.8% (262/268) of the patients in this study were discharged early with a drain, but with lack of discharge guidance. Conclusion Disadvantages of portable disposable low pressure vacuum drainage system include puncture site bleeding, drainage tube cannot be extubated independently and measurement cannot be done independently, and insufficient discharge guidance. Improvement of puncture device, use of double-lumen tube independent drainage, and improvement of discharge guidance should be made to improve the system.