Abstract: Aimed to the field characteristics of agricultural public service motivation, this study selected research routeof social psychology in synthetic agent paradigm, from three aspects of the actors, the behavior of the object, and social systems environment, to examine motivation and constraints of agricultural public service by science and technology workers in agricultural and forestry colleges. In this stage, we need to fit the responsibility motivation, requirement motivation and Institutional environment motivation of agricultural public service, aimed at constraints including responsibility empty,limited ability to undertake and lack of encouragement, should strengthen motivation and defuse resistance to enhance the agricultural public services level by science and technology workers in agricultural and forestry colleges.