The invention discloses a well washing sampling pump for an environment monitoring well, the structure of the well washing sampling pump comprises a main body, a base and a top cover, the bottom of the main body is provided with the base, the top cover is clamped at the top of the main body, the main body comprises a heat dissipation shell, a rear clamping cover and a water pumping device, the water pumping device comprises a rotating impeller, a water inlet and a water pumping groove, and the rotating impeller comprises a rotating shaft, an impeller and a sealing device. The impeller comprises an impeller body, a friction block, an inlet groove and a sand discharging opening, the sand discharging opening comprises a sand discharging groove, an elastic piece block and a deformation groove, the impeller is driven by the rotating shaft to rotate anticlockwise, so that water flow and silt mixed in the water flow can directly enter the inner side of the impeller, and the impeller pushes the water flow and the silt to flow into the water pumping groove; friction between impeller rotation and silt can be reduced, the rotation speed of the impeller is increased, and the extraction speed of the silt mixed in water is increased.