This study was aimed at examining the relationships among the psychosocial characteristics and the adoption of student-centered teaching technique of social studies teachers in secondary schools of the educational region I under the General Education Department. 
              The research had two main objectives : (1) to study the psychosocial variables which related to the teachers' intention to adopt and their adoption of the student-centered teaching technique (2) to study the relationship between the intention to adopt and the adoption of the student-contered teaching technique. 
              The total subjects were 200  teachers of the secondary schools in Samuthprakarn and Pathumthanee provinces. These teachers were the representatives of the social studies teachers in the educational region I. One hundred one teachers were males and ninty-nine were females. Age ranged were between 23-54  with average of 38 years. One hundred thirty-six teachers were from large size schools, fifty teachers from midium size schools and fourteen teachers from small schools. 
               There were 3 sets of veriables investigated: (1)  the adoption of teaching innovation which composed of 2 components namely, the intention to adopt and the adoption of the student-centered teaching technique (2) The psychosocial characteristic variables were attitude toward the adoption of student-centered teaching technique, subjective  norm, 
achievement motivation, internal locus of control and perception of social support and (3) the biosocial background variables of teachers including sex, age period of teaching employment, school size and amount of the knowledge in teaching innovation which the teachers possessed. 
                Four main findings were as follows: 
                Firstly, the older female teachers had the intention to utilize the student-centered teaching technique more than other groups, especially the older male teachers. The male teachers who teached in a midium size school had indeed adopted the teaching technique more than the male teachers who teached in a large size school. In addition, it was found that the female teachers who had longer period of teaching employment were the highest group on the  adoption of  the teaching technique compared to all conunterparts. 
              Secondly, the teachers' amounts of  knowledge in teaching innovation were related to the intention to adopt and the adoption of the teaching innovation. It could be said that the more the teachers had knowledge of teaching innovation, the more they would have intention to adopt and the adoption of the teaching innovation. 
               Thirdly, the finding revealed that the two psychosocial variables namely, the teachers' attitude toward the adoption of teaching innovation together with the subjective norm could explain 22 % of the variance in the intention to adopt the teaching innovation. By the subjective norm carried higher regression weight than the attitude variable. However the result showed that the subjective norm alone could explain 9 % of the variance in adoption of the teaching innovation. It also found that the teachers' intention to adopt the teaching innovation was related to the adoption of teaching innovation. These findings partially confirmed the theory of reasoned action (Ajzen and Fishbein. 1980) 
                    Finally, in perdicting the intention to utilize and adoption of teaching innovation, three psychosocial characteristics (achievement motivation, internal locus of control and perception of social support) significantly increased explained variance from 22 % using the attitude toward the teaching innovation and the subjective norm as predictor to 45 %. The regression weight of achievement motivation was the highest for the perdiction of the intention to utilize teaching innovation. The regression weight of perception of social support was the highest for the perdiction of the adoption of teaching innovation. 
                    From the findings, it was recommended that more attention should be given to the following types of teachers : the older male teachers, the younger female teachers and the younger teachers with shorter period of teaching employment. These groups of teachers should obtained directly or indirectly more knowledge and information concerning the teaching innovation. A training program should be  arranged to stimulate their achievement motives and their attitude toward adoption of teaching innovation. The school administrators and head-staffs should be informed about the necessity of social support they could provide to heighten the teachers' intention and acceptance of teaching innovation.