Objective To analyze the changes of diet and nutrition intake in gastric cancer patients of different ages after gastrectomy. Method A total of 106 patients with partial gastric cancer who underwent gastrectomy in the First Affiliated Hospital of Xinjiang Medical University from January 2021 to January 2023 were selected and divided into 89 patients in the non-elderly group < 60 years old and 17 patients in the elderly group ≥60 years old . The intake of energy carbohydrate protein and fat before surgery 1 month and 3 months after surgery were compared between the two groups. And the decrease rate of energy carbohydrate protein and fat intake 1 month and 3 months after surgery. Result The intake of energy carbohydrate and fat in the non-elderly group was decreased one month after surgery P<0. 05 and the protein intake in the elderly group was decreased one month after surgery 64. 09±10. 85 g / d compared with that before surgery 71. 21±8. 76 g / d P<0. 05 . Fat intake 43. 55±8. 66 g / d and 46. 74± 9. 70 g / d in the elderly group at 1 and 3 months after surgery were lower than those before surgery 52. 45±6. 61 g / d P<0. 05 . Fat intake 49. 56±9. 82 g / d and 52. 88±10. 88 g / d in the non-elderly group was significantly higher than that in the elderly group 43. 55±8. 66 g / d and 46. 74±9. 70 g / d at 1 month and 3 months after surgery P<0. 05 . The decrease rate of protein and fat intake in non-elderly group was significantly lower than that in elderly group one month after operation P<0. 05 . Conclusion The damage to protein and lipid intake in elderly patients with gastric cancer undergoing gastrectomy is more significant compared to non elderly patients. This suggests that targeted dietary and nutritional guidance can be provided according to the patient's age in clinical treatment of gastric cancer or it can improve the patient's rehabilitation efficiency.