The aim of this study is to examine teachers' motivation as a great mediator for teachers' readiness in applying ICT in their teaching and learning. Apart from that, this study was carried out to differentiate the influence of exsogenous variables from the endogenous variables based on the academic fields (pure science and social science). This is a quantitative study using a survey method, involving a total of 874 high school teachers in Indonesia, including 446 science teachers and 428 social science teachers. Data was analyzed using path analysis (path analysis/ SEM) with AMOS software version 18. The results show that motivation is a significant variable as a mediator between the variables of readiness with ICT application in teaching and learning science and social science. Analysis of structural equation path model (SEM) shows that the data used in this study has a reasonable suitability for the proposed regression model. Thus, it is proved that the two independent variables are linked directly and indirectly to the dependent variable of the study which is the application of ICT in teaching and learning. The implication of this study is that the goverrnments and ministry of educations take into account teachers attitudes and motivations in terms of ICT application and address this issue by providing suffcent infrastructure, equipments, facilities, and training for teachers to develop positive attitudes the towards ICT use in education.