The invention discloses a test piece structure for generating high-speed liquid drops with a high-speed jet flow. The test piece structure includes: a jet flow nozzle, a round-shaped wheel disc, and a plurality of step-shaped baffle pieces that are uniformly arranged circumferentially on the wheel disc. A wedge slit is formed between each two adjacent step-shaped baffle pieces. A square-shaped trough is communicated with the wedge slits. During test, a square-shaped test piece is disposed in the square-shaped trough, and the jet flow nozzle directly faces to the wedge slits so as to jet high-speed liquid drops onto the square-shaped test piece, thereby forming dispersed high-speed liquid drops on the surface of the test piece. In the method, the structure of the square-shaped test piece is adjusted so as to convert high-speed jet flow impact into high-speed liquid drop impact, so that in one test process, the anti-water-erosion performance of the high-speed liquid drop impact and the high-speed jet flow impact on a material can be researched at the same time, thereby simulating actual operation status of steam turbine blades. On the basis of guaranteeing safe and stable operation of the test system, a steam turbine blade material anti-water-erosion performance test being close to actual operation status can be carried out, thereby providing necessary theoretic basis for design and researching of the steam turbine blades.