Abstract: Developing pest control professional service organizations and accelerating the promotion of new pest control machinery are China’s policy orientations to improve pesticide utilization rate and to achieve pesticide reduction. Based on the farmer behavior theory and a sample survey data of 320 farmers in the Manas River Basin of Xinjiang, this paper applied a Probit model to analyze farmers’ decision-making behaviors on outsourcing for pest control machinery and the influencing factors. Results show that the sprayer is the most important type of pest control tool in the sample area and farmers mainly use large and medium-sized pest control machinery such as sprayer through outsourcing services. The outsourcing of pest control machinery has reduced the amount of pesticide applications on corn and cotton production. The decision of farmers’ outsourcing services of pest control machinery is influenced by operation scale with a U-shaped trend. Farmers have the highest probability of outsourcing when their land scale ranging from 2 hm2 to 10 hm2, exceeding 50%. Plot scale, unified irrigation of adjacent plots, male number and non-agricultural labor force ratio have significant positive impacts on farmers’ outsourcing services. Agricultural technical training has significant negative impacts on the demand for outsourcing services. Considering that the quality of outsourcing is difficult to monitor and has high quality risk, the model also includes variables such as risk attitude and agricultural insurance, but the impacts are not significant. In summary, this paper suggests to subsidize those large and medium-sized pest control machinery operations to promote the development of the outsourcing market, to promote professional outsourcing services in a timely manner in accordance with the development status of regional scale operations, and to appropriately organize joint outsourcing operations among farmers combined with the control of pest systematically, innovative outsourcing service supply system, standardized services, and improved monitoring system.