Vitamin D is fat⁃soluble vitamin, which can stimulate the absorption of intestinal calcium and phosphate, absorb renal calcium and phosphate, and regulate the metabolism of bone minerals.Vitamin D deficiency easily leads to rickets, steomalacia, osteoporosis, and hand and foot spasm; excessive intake of vitamin D can cause vitamin D poisoning. It mainly comes from skin synthesis and food. Frequent sun exposure is the best source for obtaining adequate and effective vitamin D. Adults are often exposed to sunlight, generally do not develop vitamin D deficiency disease. In recent years, it has shown that vitamin D is related to the development of multiple malignant tumors. It is mainly focused on two points, one is to observe the relationship between vitamin D levels in different groups and malignant tumors, and the other is whether artificial vitamin D supplementation will change the incidence of malignant tumors. This paper reviews the relevant studies between vitamin D and various malignant tumors such as colorectal cancer and skin cancer, and the results found that there is a lack of sufficient evidence to support the body′s higher vitamin D levels, which can reduce the risk of malignant tumors. Since there are few studies on vitamin D and tumor development and development, and the results are vulnerable to climate, geographical environment, dietary factors, further prospective studies of large samples may be needed to further clarify the relationship between vitamin D and tumor.