A sampling device and method for evaluating ecological risk of soil in a high geological background area comprises an impact sampling mechanism, a soil layer stripping mechanism and an auxiliary support frame. The impact sampling mechanism comprises a sampling hopper with a downward opening. A connecting sliding rod is fixedly arranged on the top of the sampling hopper. An upper end of the connecting sliding rod is connected with an impact rod. The impact rod is internally provided with an impact hammer capable of reciprocating along an axis of the impact rod. The soil layer stripping mechanism comprises a stripping sliding cylinder in sliding fit with the connecting sliding rod, and a support disc. A plurality of stripping plates are connected to a lower side edge of the support disc in a sliding fit mode.