Provided is a method for producing a DDR type zeolite crystal, the method including: a raw material solution preparing step of preparing a raw material solution by mixing at least silica, water, an organic solvent, and 1-adamantanamine that is a structure directing agent; and a DDR type zeolite crystal generating step of generating a DDR type zeolite crystal by performing a heating treatment on the raw material solution, in which the organic solvent is an organic solvent containing no amine, and the raw material solution is a raw material solution containing no PRTR substance.