A passive method is provided as alignment means for aligning an optical fiber with an optical element in assembling an optical module, while increasing alignment accuracy. A mount (28a) equipped with an optical element (3a) is positioned by abutment on a face (33c) of a projection (33a) formed inside a package (33) and on a side (33g) of a positioning pad (37) projecting from the bottom (33f) of the package. A mount (28b) equipped with an optical element (3b) is positioned by abutment on an inner wall (33b) of the package and on a face (33i) of a projection (33c) formed inside the package. Since the optical power of received or emitted light need not be monitored for fine adjustments of alignment, this method is less expensive.