This study was intended to investigate the developmental tendencies of motor ability in children as measured by various items of pass-or-fail type. Total of 612 pupils (317 boys and 295 girls), ranging in age from 6 to 12 years, were tested by 67 items partly revised from Kano's motor ability test, during the period from Nov. 1976 through Mar. 1977. The test consisted of such items as body balancing, body coordination, manual dexterity, reverse action of arms or legs, and imitating. The results were summarized as follows: 1. In general, the developmental tendencies of the motor ability were classified into 8 types, which seems to be in agreement with the result obtained in the preceded studies. 2. Boys were superior to girls in such items as ball throw and catch, but were inferior, especially in pupils of the lower grades, in nervous control of fingers and rhythmical movement of body. 3. In comparison with the preceded study (Masaki 1961), the higher percentage of pass was found in such items as ball handing and jump as well as writing speed and scissors manipulation. Decrease in percentage of pass was observed on items concerning body balancing and performance with eyes closed. 4. As a whole, the development of motor ability in the present study was remarkably accelerated in the lower grades in comparison with the original data in which these tests were standardized 30 years ago.