The author of the present paper investigated the small oscillations of temperature and humidity using the thermogram and hygrogram obtained at the Miyakozima Meteorological Station. The small oscillation of temperature begins to appear at sunrise and disappears in night hours, and its frequency of appearance shows maximum at about 12-14h. The frequency of small oscillation of humidity is analogous to that of temperature, and when it is windy it appears also in night hours. Further, it is found that these small oscillations are closely related to the solar radiation and the wind velocity.