OBJECTIVE In Japan, distal gastrectomy is the most common operation performed to treat gastric cancer. However, this procedure often leads to postoperative problems such as weight loss. METHODS We assessed the changes of nutritional status early after operation and the associations of the postoperative body weight (as a percentage of the preoperative weight) and background factors in patients who underwent distal gastrectomy. We measured the changes of nutritional indices (mean body weight, TSF, AMC and Alb) and nutrition intake on the day before operation (before operation), before postoperative resumption of oral intake (before oral intake), and on the fifth day of a soft rice porridge diet (after soft rice). Background factors included gender, age, preoperative BMI and preoperative exercise. RESULTS Mean body weight, TSF, and AMC significantly decreased from before operation, to the day before oral intake and to the day after soft rice. The postoperative body weight was not associated with the gender, age, or preoperative BMI. The frequency of regular preoperative exercise was associated with the postoperative body weight. The total daily calorie intake was 1,664 kcal (before operation), 398 kcal (before oral intake), and 949 kcal (after soft rice). CONCLUSIONS To conclude, nutritional status changes significantly after distal gastrectomy. Early nutrition intervention may be needed in patients who undergo distal gastrectomy for gastric cancer.