[Objective] The effects of farmers' behaviors on soil erosion were researched to provide basis for protecting and improving the ecological environment of mountainous area of Northern Guangdong Province, and for realizing precisive poverty alleviation and regional sustainable development.[Methods] This paper focused on farmers' behaviors who confronted with poverty situation lived in the northern mountainous area of Guangdong Province. Method of participatory rural appraisal(PRA) was adopted to carry out survey. Pressure-status-response(PSR) model was established to study the effects of farmers' behaviors on soil erosion evaluation index system. From the perspective of farmers' behaviors, analytic hierarchy process was used to determine the weight of each index.[Results] (1) Owing to the decrease of firewood dependence and slope land cultivation, the stress effect of farmers' behaviors on soil erosion were descended from 2012 to 2016. (2) Although the state value of farmers' behavioral effects on soil erosion was declined, the state value of farmers' participation in soil and water conservation was increased, these two sub-items led to the increase of total state value. (3) Both of farmers' and government's response value to soil erosion control were gradually increased. (4) In terms of all the PSR values, influence effects of farmers' behaviors on soil erosion were slightly decreased, whereby local ecological environment had getting better.[Conclusion] The farmers' influence with respect to pressure values on local soil and water conservation was decreasing, while the state value was increasing. The farmers'influence value on the soil and water conservation experienced slight decreasing ultimately, and the farmers' influence on soil and water conservation was reducing.