The organization system of agricultural extension is the first method to transfer and disseminate new technologies in the agricultural sector. This has led to play an important role to promote the development process. The main strategy of the organization system of agricultural extension  program is to promote, increase awareness, knowledge and proficiency farmers by extensional training courses. The purpose of this study was to investigate the role of extensional trainings courses on acceptance of intergraded rice - fish culture in Guilan province. The study population consisted of two groups of farmers in Guilan. The first group including rice farmers who cultivated only rice and the second group who cultivated rice with fish (integrated rice-fish culture). The sample size was calculated using Cochran formula. The sample size was selected 100 and 135 for the first and the second group, respectively. A questionnaire was used to collect information. For reliability of questionnaire krunbakh test was used. The number of krunbakh test obtained 0.86. The results showed there was no significant correlation between the individual characteristics (age, family size, experience rice farming and land holding) with acceptance of integrated rice- fish culture. But there was significant correlation between level of education, participating in training extension courses, attitude to rice-fish farming and knowledge of rice-fish cultue with acceptance of rice - fish culture.