Objective To explore the influence of structured lipid emulsion on acute phase protein and acute inflammatory reaction in gastrointestinal cancer patients after operation.Methods Eighty postoperative patients with gastrointestinal caner from July 2010 to February 2012 were randomly divided into observation group and control group,and 40 cases for each group.Patients in observation group were given structured lipid emulsion,while in control group were given physic mixture of medium-chain/long-chain triglycerides group.Meanwhile patients in both groups were received isonitrogenous and isocaloric parenteral nutrition for 6 days after operation.The general conditions after operation were recorded.Acute phase protein and acute inflammatory reaction were measured before operation,the 1 st day and 7th day after operation.Results After 6 days parenteral nutrition,the vital sign data,blood routine indices,liver and renal function,blood fat were back to normal values in two groups.There was no significant difference in the incidence of postoperative infection complication and hospitalization duration between observation group and control group (12.5％ (5/40) vs.25.0％ (10/40) ; (12.9 ± 0.7) d vs.(13.1 ± 0.9) d; P ＞ 0.05).The serum levels of Albumin (ALB),Prealbumin(PAB) and Transferrin(TRF) on the 1st day after operation in two groups were significantly lower than those before operation,while the serum levels of C reactive protein (CRP) and fibrinogen (Fib) were significantly higher,then gradually recovering.The serum levels of ALB,PAB,TRF,CRP,Fib on the 7th day after operation in observation group were (37.11 ± 3.30) g/L,(0.25 ± 0.08) g/L,(2.35 ± 0.49) g/L,(21.84±16.76) mg/L,(3.95 ± 1.23) g/L,significant different from those on the 1st day before nutrition therapy ((31.52±2.92) g/L,(0.15 ±0.02) g/L,(1.90 ±0.54) g/L,(83.80 ±47.13) mg/L,(4.35 ±0.98) g/L) and control group ((34.50 ±2.71) g/L,(0.18 ±0.05) g/L,(2.00 ±0.52) g/L,(41.36 ±23.49) mg/L,(4.76 ± 2.35) g/L; P ＜ 0.05).The serum levels of interleukin (IL)-1,IL-2,IL-6,tumor necrosis factor (TNF)-α decreased on the 1st day after operation of two groups,then gradually increasing.The serum levels of IL-2,IL-6 on the 7th day after operation in observation group were (987 ±203) ng/L) and (277 ± 107) ng/L,significant different from those on the 1st day before nutrition therapy ((890 ± 197) ng/L and (355 ± 107) ng/L;P ＜0.05),and lower than those in control group ((1 347 ± 195) ng/L,(752 ± 187) ng/L; P ＜0.05).The serum levels of TNF-α on the 7th day after operation in observation group was (197 ±98) ng/L,which was as same as that on the 1 st day before nutrition therapy ((167 ± 79) ng/L,P ＞ 0.05) and lower than this in control group((342 ± 106) ng/L;P ＜0.05).Conclusion Structured lipid emulsion can effectively improve the synthesis of acute phase protein in gastrointestinal cancer patients after operation,regulate the inflammatory cell factors producing and releasing,which is benefit to smoothly through stress reaction period.