OBJECTIVES Studies on the ecology of medical care have provided a framework for health care systems, medical education, and clinical research. Ten years ago, Fukui et al. reported the ecology of medical care in Japan. However, medicine and health care organization has changed since then. In the current study, we conducted an updated evaluation and compared it to results observed 10 years ago to understand health care seeking behaviors of people in Japan. METHODS A population weighted random sample from a nationally representative panel was used to estimate the number of health-related symptoms, self-care, and health care utilization per 1,000 individuals based on a prospective health diary recorded for one month. Variations in terms of age and gender were also examined. RESULTS Based on 4,548 persons (3,787 adults and 797 children), on average per 1,000 persons, 794 (95% Confidence Interval (CI): 782 - 805) had at least one symptom, 447 (95% CI: 433 - 462) used over-the-counter drugs (OTC), and 265 (95% CI: 252 – 278) visited a physician’s office, 206 (95% CI: 194 – 218) a primary care physician, 4 (95% CI: 2 - 5) a hospital emergency department, and 117 (95% CI: 107 - 126) a professional provider of complementary or alternative medical (CAM) care. Children had more physician visits, and adult used more OTC and CAM. Females were more likely than males to have symptoms, to visit their physician and to use OTC and CAM. CONCLUSIONS Compared with the data from 2003, health care seeking behaviors of people with symptoms in Japan are remarkably similar, with the exception of an observed increase in the use of CAM. Results of this study would be useful for further delineation of health care seeking behaviors of people in the context of a health care system unique to Japan.