Objective To investigate the effect of subcutaneous placement of negative pressure drainage tube on prevention of incision infection after exploratory laparotomy in obese patients. Methods Select a comparable emergency laparotomy in 240 cases of obese patients, incision type both class II and class III incision, were randomly divided into experimental group and control group 120 cases, incision suture in experimental group subcutaneous negative pressure drainage tube, the control group routine suture, observe two groups of patients with wound healing. Two, the rate of incision infection, suture and hospitalization. Results Wound healing in experimental group was 110 cases, 90 cases in the control group, the experimental group was significantly higher than the control group (P<0.01); 3 cases of wound infection in the experimental group, 11 cases in the control group, the experimental group was significantly lower than the control group (P<0.05); two suture in 2 cases in the experimental group, 9 cases in the control group, the experimental group was significantly lower than that of the control group (P<0.05); hospitalization time of the experimental group was 7.72 + 3.144 days, the control group was 12.28 + 4.512 days, the experimental group was significantly lower than the control group (P<0.01). Conclusions Obese patients with emergency laparotomy II class and III class incision suture incision subcutaneous negative pressure drainage tube can improve the healing rate of incisions, decrease the infection rate of incision, suture two reduction rate and shorten the hospitalization time, is worthy of further clinical application.