The manufacturing method for the fuel cell unit includes a stacking step and a laser irradiation step. In the stacking step, a stacked portion including, stacked together, a resin frame member of a resin frame equipped membrane electrode assembly and an outer peripheral portion of a separator is placed on a metal spacer. The resin frame member at a joining target portion of the stacked portion is placed so as to face a recess of the metal spacer. In the laser irradiation step, the separator at the joining target portion in a state where the resin frame member faces the recess is irradiated with a laser beam to thereby form a welded portion where the resin frame member and the separator are welded to each other.