Epidemiological evaluation of rural population samples of Misasa, Tomari and Kofu villages in Tottori Prefecture, Japan (Fig. 1), for occurance of rheumatic disorders was performed. This region has an annual rainfall of about 80 inches. The principal occupations are farming, and fishery in part. 1. One thousand six hundreds and twenty-seven persons, age 30 and over were investigated by clinical and serological means. In this preliminary communication the prevalence of probable and definite rheumatoid arthritis, accoding to defined by the A.R.A. criteria, was 1.04% and low back pain-sciatic pain, arthralgia and painful shoulder (cervical spondylosis and so on) were 8.4, 8.9 and 7.1% respectively (Table 2 and 4). 2. Serum samples from residents in Misasa- and Tomari-districts were obtained and rheumatoid factor was tested by means of RA-test (Hyland Laboratories). The incidence of positive test was 3.2% in 407 males and 5.0% in 715 females, but there is no significant difference between the two. Concerning the effect of age, there was a general tendency for the proportion of positive test to be greatest in the older age groups (Fig. 2). 3. Serum uric acid concentrations of 230 males and 395 females were measured by the modified method of Folin-Wu (latron-kit-method). The mean serum uric acid concentration (with standard deviation) was found to be 4.02±0.18mg. per 100ml. for males and 3.38±0.13mg. per 100ml. for females (Fig. 3 and 4), and the differecne between the two was significant. The author found no gouty patient in this papulation survey.