Abstract: A method for preparing a shielded gate semiconductor device structure, and a shielded gate semiconductor device structure. The following steps are added in between source polycrystalline silicon deposition and gate polycrystalline silicon oxidation: removing, by etching, a first oxide layer and a second oxide layer that are in a middle upper space of a cell trench and on the surface of a semiconductor material layer, and a portion of the semiconductor material layer between trenches; removing, by etching, the gate polycrystalline silicon until a thickness of remaining gate polycrystalline silicon in the source lead-out region trench reaches a preset thickness; and selectively removing, by etching, remaining gate polycrystalline silicon in the source lead-out region trench until no gate polycrystalline silicon remains in the source lead-out region trench, and then removing the photoresist.