The purpose of this study is to identifying effective components in transformation agricultural extension system in Iran, that using mixed-method approach which was carried out in four steps. In the first step of the study, the components of transformative agricultural extension system in some countries (15 countries) were examined by using meta-synthesis of qualitative research methods. In this step 11 components were extracted that included centralization, privatization, extended information technology, demand-driven, consultative services, pluralistic extension, strengthening interaction between extension and research centers, policy reform, environmental support, knowledge management and increasing coverage of rural areas. Second step was conducted by using the Delphi technique and viewpoint of experts of the agricultural extension organization and faculty members in agricultural college in Tehran, TarbiyatModares and Shiraz (N= 55) and the agreementsof this target population about identified effective components in step one, was obtained. The results of this step showed that the components of the strengthening of interaction between extension & research, policy reform, pluralistic extension, decentralization and investment, there were more than 90 percent agreements. In the third step, current situation of agricultural extension system was analyzed by experts of agricultural extension organization by using quantitative method and it was determined that the current system of agricultural extension in Iran, considered in decentralization, privatization and strengthening of interaction, more than other components of interest. Finally, in the fourth step, by integration of three previous steps, theory of transformational agricultural extension system based on Strauss and Corbin model, by using qualitative method was obtained.