Background: Laparoscopic surgery produces lesser postoperative inflammation with a smaller cytokine and leptin response, and might thus reduce postoperative anorexia compared to open surgery. The aim of the present study was to determine the role of serum leptin in postoperative anorexia after laparoscopic gastric cancer surgery. Methods: Fifty-four consecutive patients with adenocarcinoma of the stomach were operated on either with open or laparoscopic surgery. Correlations were determined between the serum levels of leptin, clinico-pathological characteristics, serum haemoglobin and albumin. Results: Serum leptin levels on day seven were correlated significantly to gender (p=0.004), BMI (p=0.002) and tumour grade (p=0.033). In the patients with CRP < 100 mg/l the leptin levels on day seven were significantly lower after the laparoscopic operation (p=0.042) and in patients with lower BMI (p=0.001). The linear regression model determined a significant correlation between the relative concentration of leptin on day seven and laparoscopic surgery (Beta -0.688; p < 0.0001), gender, BMI, location of the tumour, T stage, N stage, perioperative therapy, tumour grade, perineural invasion, Lauren histological type and ulceration. In patients with CRP levels below 100 mg/ml the serum level of albumin on day seven after surgery was significantly higher in patients after laparoscopic surgery. Conclusion: Laparoscopic surgery produced significantly lower relative leptin concentrations on day seven, and higher serum albumin levels in the subgroup with CRP levels below 100 mg/l at discharge. These results suggested that laparoscopic gastric cancer surgery might reduce postoperative leptin response, leading to a better nutritional status at discharge compared to open surgery.