Objective To study the application method and effect of perioperative enteral nutrition support in patients with gastrointestinal cancer.Methods 82 patients with gastrointestinal tumor were randomly divided into two groups.41 cases in the control group were given intravenous nutrition.41 patients in the study group were given enteral nutrition support 7d before operation,outage on the day of surgery,postoperation consistently given enteral nutrition support for 7d.The preoperative nutritional status,immune index,postoperative complications,the length of time and hospitalization expenses were compared between the two groups.Results Preoperative 1d,7d,the ALB,TRF,TP, PAB levels in the study group had no statistically significant differences compared with admission (all P >0.05).7d after operation,the TRF,PAB of the study group were (1.71 ±0.17)g/L,(174.67 ±22.81)mg/L,which of the con-trol group were (1.46 ±1.46)g/L,(142.73 ±27.32)mg/L,the differences were statistically significant (t =2.662, 2.917,all P <0.05).3d,7d after operation,the CRP,IL -6 and TNF - levels in the two groups increased signifi-cantly,compared with preoperation the differences were statistically significant (P <0.05).3d,7d after operation,the team CRP levels of the study group were (121.5 ±15.6)mg/L,(55.17 ±7.62)mg/L respectively,IL -6 levels were (81.42 ±13.56)pg/L,(56.14 ±9.73)pg/L and TNF -levels were (67.25 ±17.23)pg/L,(63.23 ±11.80)pg/L;In the control group,3d,7d after operation,CRP levels were (161.3 ±20.7)mg/L,(99.26 ±20.74)mg/L,IL -6 levels were (103.62 ±21.54)pg/L,(77.43 ±18.26)pg/L,the TNF -levels were (79.01 ±16.9)pg/L,(68.25 ± 12.48)pg/L,the differences between the two groups were statistically significant (P <0.05).The incidence rate of complications of the study group was 2.44%,which of the control group was 12.20% (χ2 =2.717,P <0.05 ). Conclusion Gastrointestinal tumor patients with malnutrition,perioperative enteral nutrition support can promote the synthesis of protein metabolism,relieve excessive postoperative systemic inflammatory reaction,reduce the risk of surgery.