Objective To investigate the effect of nutritional support on prognosis of alcohol dependent patient. Methods Alcohol dependent patients hospitalized in Mental Health Center of the First Hospital of Hebei Medical University from August 2018 to December 2020 were selected. The nutritional risk screening scale （NRS2002） was used to screen the nutritional risk of the patients. A total of 116 patients with nutritional risk （NRS≥3） were included. The patients were divided into nutritional support group （n=70） and non nutritional support group （n=46）. The clinical outcomes and complications were compared between the two groups. Results The average duration of delirium in nutritional support group ［（51.32±9.93）h］ was lower than that in non nutritional support group ［（60.06±13.14）h］. The difference was statistically significant （t=-2.290， P=0.028）. The Activities of Daily Living （ADL） scores of the nutritional support group on the 3rd and 7th day after admission ［（89.71±16.83），（94.43±11.60）］ were higher than those of the non nutritional support group ［（80.54±21.51），（88.37±14.61）］. The difference was statistically significant （F=6.955， P=0.012； F=6.153， P=0.015）. The complication rate of nutritional support group was 21.4% （15/70）， which was lower than that of non nutritional support group ［39.1% （18/46）］. The difference was statistically significant （χ2 =4.273， P=0.039）. Conclusions Nutritional support can reduce alcohol withdrawal reaction， shorten the duration of delirium， promote the recovery of life ability， and reduce the complications of infection， pressure sores， falls and other complications.