Abstract: Malignant tumors are major chronic diseases that seriously endanger the health of Chinese residents. Investigations on tumors and risk factors are important foundations for tumor prevention and control strategies in China. Epidemiological investigations on tumors in China began in the 1970s. The regions with high incidence of tumors are identified through three national retrospective cause-of-death investigations. Then a large number of investigations on tumor-related risk factors have been carried out, making important contributions to the development of comprehensive strategies for tumor prevention and control in China. This paper systematically reviews three national retrospective cause-of-death investigations focusing on tumors, five investigations on tumor-related risk factors, and six investigations on high-incidence tumors and their risk factors that were conducted in China in the past half century. The current situation of epidemiological investigation on tumors and risk factors in China under the background of the new era has been sorted out, and the related work has been further prospected. The aim of this review was to better publicize and implement the Cancer Prevention and Control Actions of the Healthy China Action (2019—2030), continue to strengthen the investigation and research of tumor prevention and control in China, pay attention to etiological prophylaxis of tumors, and advance the frontier.