Objective To investigate the nutritional support of hospitalized patients with advanced lung cancer in Shanghai. Methods From July 2018 to May 2020, hospitalized patients with advanced lung cancer in our hospital were selected. Patients were assessed using general situation questionnaire and patient subjective evaluation scale. The experimental indicators of patients were detected, the nutritional support was analyzed, and the risk factors of nutritional status of patients with lung cancer were analyzed. Results Among the 106 patients, 75 were male and 31 were female, 74 were under 64 years old and 32 were over 65 years old; PG-SGA results revealed that 37 cases (34.91%) scored 0~1, 48 cases (45.28%) scored 2-8, and 21 cases (19.81%) scored equal to or above 9; According to PG-SGA classification, patients were divided into good nutrition group (n=37) and malnutrition group (n=69). The proportion of patients of ≤64-year-old, TNM stage IV, WBC and neutrophil count in good nutrition group was lower than that of malnutrition group (P<0.05), meanwhile, the KPS, body mass index, red blood cell count, lymphocyte count, hemoglobin, serum protein, albumin, immunoglobulin IgG, IgM, IgA, CD4 +, CD3 +, and CD8 + were higher than those of malnutrition group (P<0.05). Logistic analysis showed that age ≥ 64 years old, TNM stage IV, KPS and BMI were risk factors of nutritional status (P<0.05). Conclusion Among the patients with advanced lung cancer in Shanghai, the incidence of malnutrition is 65.09%, and 19.81% of those with severe malnutrition are in urgent need of nutritional support. Logistic analysis results yield that age over 64 years old, TNM stage Ⅳ, KPS, body mass index are risk factors affecting nutritional status of patients.