Objective To explore the correlation between serum vitamin levels and clinical pathology and other factors in lung cancer. Methods The clinical data of 549 inpatients with pulmonary nodules/lung occupation in a large-scale general hospital from September 2020 to May 2022 were retrospectively analyzed. The differences in serum vitamin levels were compared between patients with benign and malignant pulmonary nodules and among those with different pathological types of lung cancer. Logistic regression analysis was used to evaluate the correlation between serum vitamin levels and the risk of lung cancer of different pathological types. SPSS statistics 26.0 was used for statistical analysis. Data comparison between 2 groups was performed using student′s t test, Wilcoxon test or Chi-square test depending on data types. Results Among the 549 subjected patients, 29 cases (5.3%) were diagnosed as benign lung nodules by pathology and clinical diagnosis, 56 cases (10.2%) as small-cell lung cancer (SCLC), 464 cases (84.5%) of non-small-cell lung cancer (NSCLC). Compared with the patients with benign lung nodules, the serum levels of vitamin A, vitamin B₁, vitamin C and vitamin D were significantly lower in lung cancer patients (all P<0.01). For the lung cancer patients, the serum vitamin A and vitamin C levels were obviously lower in the females (both P<0.01). The serum vitamin B₂ and vitamin D levels were notably lower in the SCLC patients than the NSCLC patients (both P<0.05). In the NSCLC patients, the vitamin C level was notably lower in the adenocarcinoma patients than those with squamous cell carcinoma (P<0.05). The serum levels of vitamin A, vitamin B₂, and vitamin D were remarkably lower in the patients with intermediate and advanced NSCLC (stage Ⅲ and Ⅳ) than those with early NSCLC (all P<0.05). Logistic regression analysis showed that serum vitamin A deficiency (OR=0.220,95%CI 0.126-0.385; P<0.001) and vitamin B₁ deficiency (OR=0.963,95%CI 0.938-0.988; P=0.004) were independent risk factors for lung cancer. Serum vitamin A deficiency (OR=2.433,95%CI 1.007-5.878; P=0.048) and vitamin B₂ deficiency (OR=1.780,95%CI 1.115-2.843; P=0.016) were independent risk factors for SCLC. Serum vitamin C deficiency (OR=0.932,95%CI 0.889-0.977; P=0.004) and vitamin D deficiency (OR=0.967,95%CI 0.948-0.986; P<0.001) can be used as an independent risk factor for advanced NSCLC. Conclusion Vitamin deficiency is quite common in patients hospitalized due to lung cancer. Some serum vitamin indicators may be independent risk factors for the development and progression of lung cancer.