The invention discloses a monitoring system for the migration of elements of nitrogen, phosphorus and the like in the hydrologic cycle process of farmland soil. The monitoring system is provided with a water supplying system, a soil holding pool, a water head and water level control system, a soil solution collector, a bottom frame and a slope regulator, wherein a water inlet pool and a water outlet pool of the water head and water level control system are respectively arranged near two wide side walls of the soil holding pool and share the side walls together with the soil holding pool, holes are respectively formed in the shared side walls, water level / water head control holes are respectively formed in the outer side walls of the water inlet pool and the water outlet pool, baffle plates are respectively arranged on the outer side walls of the water inlet pool and the water outlet pool, a nozzle of the water supplying system is positioned above the soil holding pool, collecting tanks of the soil solution collector are embedded in soil in the soil holding tank, and head sections and tail sections of the two adjacent collecting tanks in each line are positioned in the same plane, the soil holding pool, the water inlet pool and the water outlet pool are integrally placed on the bottom frame, and the slope regulator is arranged under the bottom frame. According to the monitoring system, the elements of the nitrogen the phosphorus and the like in the vertical infiltration process of soil water in different soil layers can be monitored, and the elements of the nitrogen, the phosphorus and the like in a shallow groundwater flowing process can be monitored.