Abstract: In farmland with shallow groundwater, groundwater makes great effects on the hydrological, biological and chemical process in Soil Plant Atmosphere Continuum. These processes, which are closely related to soil physics, hydrogeology, hydrology, agrometeorology, and plant physiology, were probed into in recent years by related scientists. This paper reviewed the development of the studies of the effects of groundwater on evapotranspiration in farmland. It concluded that groundwater aquifer should be coupled with SPAC into an integrated system, and the field experiments should be conducted to identify these processes.