A plurality of blanks divided at a division end face 5 or a blank-bonded product comprising a plurality of blanks sintered and bonded together are or is compressed in the same mold, so that they are plastically deformed until the division end faces 5 are cohered. Thereafter, a load is applied to the plastically worked product in a direction of breaking of the division end faces 5 to break the division end faces 5 and divide the plastically worked product into a plurality of members. In this manner, a split type mechanical part having irregularities meshed with each other on mating faces and easily positionable relative to each other can be produced with a good dimentional accuracy.