A method for manufacturing a photoresist structure, performed by a processing device, and comprising: forming (S101, S201) a first photoresist layer on a substrate, and performing (S101, S201) first baking; forming (S102, S202) a second photoresist layer on the first photoresist layer after the first baking, and performing (S102, S202) second baking; performing (S103, S203) under exposure to the second photoresist layer after the second baking, whereby an exposure time for the photoresist layer is less than a time required for the photoresist layer to fully react, and performing (S103, S203) third baking; developing and fixing (S 104, S204) the second photoresist layer after the third baking to determine a partially patterned second photoresist layer, the partially patterned second photoresist layer comprising a first opening, the first opening corresponding to an exposure area or a light-shielding area of the under exposure, the first opening comprising a first part and a second part located on a side of the first part close to the substrate, an aperture of the first part being smaller than an aperture of the second part, and an orthographic projection of the first part on the substrate is within an orthographic projection of the second part on the substrate; flood exposing (S105, S205) the partially patterned second photoresist layer, whereby the partially patterned second photoresist layer is fully exposed to fully react; and performing (S105, S205) fourth baking to determine a patterned second photoresist layer; and etching (S106, S206) the first photoresist layer using the patterned second photoresist layer as a mask to determine a patterned first photoresist layer. forming (S101, S201) a first photoresist layer on a substrate, and performing (S101, S201) first baking; forming (S102, S202) a second photoresist layer on the first photoresist layer after the first baking, and performing (S102, S202) second baking; performing (S103, S203) under exposure to the second photoresist layer after the second baking, whereby an exposure time for the photoresist layer is less than a time required for the photoresist layer to fully react, and performing (S103, S203) third baking; developing and fixing (S 104, S204) the second photoresist layer after the third baking to determine a partially patterned second photoresist layer, the partially patterned second photoresist layer comprising a first opening, the first opening corresponding to an exposure area or a light-shielding area of the under exposure, the first opening comprising a first part and a second part located on a side of the first part close to the substrate, an aperture of the first part being smaller than an aperture of the second part, and an orthographic projection of the first part on the substrate is within an orthographic projection of the second part on the substrate; flood exposing (S105, S205) the partially patterned second photoresist layer, whereby the partially patterned second photoresist layer is fully exposed to fully react; and performing (S105, S205) fourth baking to determine a patterned second photoresist layer; and etching (S106, S206) the first photoresist layer using the patterned second photoresist layer as a mask to determine a patterned first photoresist layer.