A method and an apparatus for determining expansion compensation in a photoetching process, and a method for manufacturing a semiconductor device are provided. A relative vector misalignment value of a first wafer and a second wafer after being bonded is obtained based on a relative position relationship between a first alignment pattern of the first wafer and a second alignment pattern of the second wafer in a boding structure. A relative expansion value of the first wafer and the second wafer is obtained based on the relative vector misalignment value. A developing expansion compensation value in the photoetching process is obtained. The expansion compensation value is used to the photoetching process of a first conductor layer including the first alignment pattern of the first wafer and/or a second conductor layer including the second alignment pattern of the second wafer.