The global evidence of the process by which farmers make decisions about participating in environmental nongovernmental organizations (ENGOs) is lacking. This study provides empirical evidence of the determinants of farmers’ intention to participate in ENGOs and benefits from a combination of the theory of planned behavior and the socioeconomic model of participation that serves as the theoretical framework of the study. Using the proportional stratified random sampling, 368 farmers were selected from the population that consists of all farmers in the southern basin of Lake Urmia (LU), northwest Iran. The research participants were surveyed via a self-implemented questionnaire. The results of the methods of confirmatory factor analysis and Cronbach’s alpha confirmed that observed variables have been properly loaded on respective latent variables. The quantitative data were analyzed using the interface of SPSS and AMOS. The author gained an impression of being fitted of the hypothesized model with the data perfectly. The results of path analysis unveil that subjective norms have a direct impact on the intention to participate in ENGOs. PBC also has a direct effect on the intention to take part in ENGOs. This variable also impinges upon the desire to participate in ENGOs and revive LU. There is a need for supportive interventions to enhance farmers’ participation in ENGOs.