This study was conducted in the districts of Guilan state of Iran to assess the impact of cooperative companies on the economic condition of rice farmers in the Guilan state. The research was conducted in the 2005 to 2007 periods. Three hundred respondents were selected for the study comprising equal number of participants and non-participants of producer cooperatives. Data were collected using survey questionnaire with a reliability test of 88% using Kronback Alfa Coefficient. Data were analysed using descriptive and inferential statistics. The results showed that there were significant differences between members and non-members with respect to the production rate of paddy, income gained through sale of rice, level of participation, reduction of unemployment, increment of annual income and technical knowledge. Also, there was a positive correlation between the rate of paddy production per hectare with income resulting from the sale thereof, the income resulting from each hectare of the rice field with the annual income of the farmer, annual income of the farmer and rate of paddy produced and on participation in training courses and the production rate of paddy. According to above points, cooperative companies have a basic role in achievement sustainable rice production and reduction of poverty in Guilan state of Iran, thus cooperative companies should be organized and supported by government.