Application of wastewater for irrigation is one of the useful approaches to alleviate the shortage of freshwater resources. Although successful implementation of wastewater-use projects depends upon the support of farmers who are affected by the project, few studies have addressed the farmers' attitude towards wastewater use and little is known about Iranian farmers' perception. Therefore, the objective of this study was to investigate farmers' attitude towards wastewater use. It was also intended to detect drivers of perceived economic benefits, and health and environmental risks of wastewater use. A survey of 108 farmers of Shiraz County, selected through a simple random sampling method, identified a number of significant knowledge gaps that currently exist among wastewater users. Furthermore, farmers articulated opposing attitudes for irrigating with wastewater. While farmers realized the contribution of wastewater to fertilize the soil and its reliability as a water resource, they were concerned about its negative impacts on health and environment. Regression analysis illustrated that a complex set of factors significantly influenced perceived risks of wastewater use, among which knowledge, closeness to wastewater canal and value orientation are the most determinant factors. Some recommendations are offered to promote farmers' awareness and attitude about wastewater and reduce its negative impacts.