Objective To explore the efficacy of low nitrogen and low calorie nutrition support in elderly patients undergoing abdominal surgery. Methods 52 patients who received abdominal surgery from January 2005 to June 2010 and were supposed not to take foods for 5 days were assigned to receive low nitrogen and low calorie parenteral nutriention ( 27 patients, group A ) or traditional parenteral nutriention ( 25 patients, group B ). Levels of blood sugar and plasma protein, incidence of complications, and costs of nutritional supplements were compared between the two groups. Results Seven days after nutritional support, the cost of nutritional supplements was significantly lower in group A than in group B( [1328.6 ±103]yuan vs[2396.8 ± 152]yuan, P< 0.01 ). The mean blood sugar values differed significantly between group A and group B ( [5.58 ± 1.34]mmol/L vs [7.17 ± 1.52]mmol/L, P< 0.05 ). There were no differences in plasma protein levels and incidence of complications between the two groups. Conclusions Low nitrogen and low calorie parenteral nutriention support is beneficial for the metabolic characteristics in elderly patients undergoing abdominal surgery and for the improvement of overwhelming inflammatory responses,reduces the incidence of complications, and accelerates the recovery of postoperative patients safely and effectively. Key words: Low calorie; Low nitrogen; Parenteral nutrition; Elderly patients; Abdominal surgery