Firstly, relying on the science and technology project of high yield in Hebei Province, connotation of agricultural technology demonstration and extension modes and the grain yield project in Hebei Province is introduced. Extension mode of agricultural technology demonstration and radiation is constructed. Agricultural technology demonstration and radiation mode includes the radiation center, primary irradiation and secondary irradiation. Secondly, management system and operational mechanism of agricultural technology demonstration and radiation mode are discussed, mainly expressed in establishing leading group of demonstration counties (cities), implementing responsibility system of department leaders, setting up expert advisory instruction group, subject technology expert group and the leading group of radiation zone, carrying out the chief expert responsibility system and the technicians matrix responsibility system, establishing the operating mechanism of “open, flow, competition and collaboration” with "test area — expert two-way selection " as the core content. Finally, countermeasures to improve the agricultural technology demonstration and radiation model is put forward, such as establishing the rural technology and demonstration base, strengthening cooperation with enterprises, and adopting flexible technical training, so as to promote the communication of agricultural high-tech, to increase the contribution rate of agricultural technology, and to offer ideas for agricultural extension model at the new era.