Abstract: Establishment of a stable extension system of agricultural machinery technology，especially grass-roots system，is basis for realizing goal of“two complete and two high”for agricultural mechanization development，and objective requirement for promoting revitalization of rural areas.Around construction of grass-roots agricultural machinery extension system，a special investigation in Jinan，Weifang，Taian，Linyi and Jining were carried out.Current situation and existing problems of construction of grass-roots agricultural machinery extension system in Shandong province were analyzed based on investigation results，and suggestions for improving service capacity of grass-roots agricultural machinery extension were put forward.