Promoting pesticide reduction is an important measure for achieving green agricultural development. This article uses a case study method and draws on the design concept of the “household responsibility system” to analyze the internal mechanism by which the “contracted responsibility system” in pest and disease control achieves pesticide reduction. The study finds that the “contracted responsibility system” provides service providers with internal motivation for pesticide reduction， incentivizing them to lower service costs by reducing pesticide consumption. At the same time， the reduction behavior of the service providers under the “contracted responsibility system” is constrained by the effect of disease and pest control， prompting them to implement timely and targeted measures to ensure effective control while reducing pesticide use. Under the “contracted responsibility system”， the service providers can not only maximize the income by reducing pesticides use， but also effectively prevent and control diseases and pests， thereby safeguarding the interests of farmers. This represents an incentivity-compatible service model. Further analysis reveals that the feasibility of promoting the “contracted responsibility system” depends on the scale of land scale management in villages and the level of interpersonal trust. Therefore， it is suggested to develop scaled operations， localize service providers， and leverage the coordinating function of village collective organizations to facilitate the smooth development of the “contracted reponsibility system” and innovate agricultural reduction strategies.