Abstract: Agro-ecosystem is the interface between human society and natural ecological system. Its healthy service function has further and actual significance in the sustainability and stability of agricultural systems and human society. In this paper, advances, connotations and contents of agro-ecosystem service are analyzed. Based on existing quantitative assessment indices and methods of agro-ecosystem service, we figure out four obstacles in agro-ecosystem service research — (1) quantification difficult of agro-ecosystem service, (2) outdated agro-ecosystem service research techniques, (3) absence or weakness of mechanisms in agro-ecosystem service research, and (4) ideological constraints to agro-ecosystem service research. Based on the above obstacles, trends of future agro-ecosystem service research are summarized. This is followed by proposing the essence of ago-ecosystem management from aspects of conception, mechanism and technology in order to function the agro-ecosystem service healthily.