Objective: To evaluate the intervention effects of parenteral nutrition with different nitrogen-content onnutriture and immune indice of patients with gastrointestinal tumors after surgery. Methods: 50 patients with gastrointestinal tumors after surgery were randomly divided into experimental group and control group with 25 patients in each group. All the patients were given total parenteral nutrition through central vein on the first day after operation, and the non-protein calorie were all 83.7-104.6kJ/(kg•d). Meanwhile, the nitrogen-content of experimental group was 0.20g(0.15-0.22g)/(kg•d), while the control group was 0.10g(0.09-0.11 g)/(kg•d). The hemoglobin, albumin, CD ₃ ⁺, CD ₄ ⁺ and CD ₄ ⁺/CD ₈ ⁺ of patients in 2 groups on the 14 ^th day after operation were compared. Results: 14 ^th day after operation, the hemoglobin, albumin, CD ₃ ⁺, CD ₄ ⁺ and CD ₄ ⁺/CD ₈ ⁺ of patients in experimental group were all obviously higher than control group (P<0.05). Conclusions: On the basis of giving the same heat quantity, total parenteral nutrition provided by normal nitrogen-content [0.20g/(kg•d)] can improve the nutritional and immune status of patients after gastrointestinal tumor surgery.