The purpose of the present paper was to investigate the relationship of "classroom structure" to "classroom climate" and "members' morale". In the first research, a Classroom Structure Scale(CSS)was developed. The CSS assessed five dimensions(reception, power, affiliation, control, activity), which were drawn as important and fundamental dimensions in elementary school classrooms. In the second research, the following problems dealt with 4-and 6-grade pupils : the interrelationship between the five dimensions and their relation to classroom climate and children's morale. There was negative correlation between the "reception" and the "power" ; The influence of the classroom structure on the classroom climate was estimated by multiple regression analysis. As for the overall classroom climate, significant multiple correlation coefficients were obtained. The main dimensions found in 4-grade classrooms were the "control" and the "reception", but the "activity" and the "reception" were the main ones in 6-grade classrooms. The relation of the structure to the members' morale was examined by computing the partial correlation coefficients. The partial correlation coefficients showed that the relation between the structure and the morale in 4-grade was different from that in 6-grade. The obtained results were discussed from the developmental point of view and some practical implications were extracted.