A method for preparing a selective emitter solar cell includes: forming a textured surface with a plurality of protrusions in the first regions and the second regions of the surface of the semiconductor substrate, wherein each protrusion has a cross-sectional shape that is trapezoidal or trapezoid-like in a thickness direction of the semiconductor substrate; performing a diffusion treatment on at least part of protrusions to form a first doped layer, and forming a first oxide layer above the first regions; re-etching the surface of the semiconductor substrate by using the first oxide layer as a mask, to etch each protrusion in the second regions to form a pyramid structure, such that the first doped layer in the second regions is etched to form a second doped layer with a doping concentration lower than a doping concentration of the first doped layer.