OBJECTIVES:  In Japan, cancer is the leading cause of death, and cancer-related health expenditures have increased, accounting for 10% of total health expenditures and reaching 23 trillion JPY. The number of cancer patients has increased due to aging of the population and the number of survivors has increased due to improved diagnosis and treatment. Although the impact on productivity loss is basic information for planning support measures, this information is unclear in Japan. We therefore estimated productivity loss for cancer survivors in Japan. METHODS:  We stratified cancer survivors as either recently diagnosed (≤1 year) or previously diagnosed (>1 year). Based on official statistics, productivity loss for outpatients, admissions and deaths was calculated. Target subjects were gastric, colorectal, lung and breast cancer survivors aged 40 years and over. Their maximum employment age was assumed to be 75 years and the discount rate used was 2%. RESULTS:  Productivity loss for gastric cancer survivors recently diagnosed was 149.9 billion JPY (18.3 billion for outpatients, 10.2 billion for admissions, and 121.4 billion for deaths). On the other hand, productivity loss for gastric cancer survivors previously diagnosed was 275.6 billion JPY (8.5 billion for outpatients, 12.7 billion for admissions, and 254.4 billion for deaths). The highest productivity loss for male survivors recently diagnosed was observed for gastric cancer at 126.5 billion JPY and that for those previously diagnosed was observed for lung cancer at 268.2 billion JPY. The highest productivity loss for female survivors recently diagnosed was gastric cancer at 23.4 billion JPY and that of those previously diagnosed was observed for breast cancer at 111 billion JPY. CONCLUSIONS:  Productivity loss for cancer survivors has become a heavy burden that cannot be ignored. Supporting measures for cancer survivors should be considered from the perspective of health economics.