A method for preparing a semiconductor sample with an etched pit suitable for microscope observation is provided, including that a semiconductor sample piece is provided, the semiconductor sample piece including a sacrificial layer and a supporting layer which are stacked, and a trench which penetrates through the sacrificial layer and the supporting layer to expose a pit on a surface of a bottom metal layer; the semiconductor sample piece is steeped by placing it in an etching solution to remove the sacrificial layer; an adhesive tape is pasted on the surface of the semiconductor sample piece after the sacrificial layer is removed; and the adhesive tape is torn to remove the supporting layer above the pit to expose the pit.