PURPOSE: To easily control marking by holding ≥1 set of plural small-sized parts by a holder also used as a jig capable of being engaged in conformity to the determined arranging direction and arranged position, and successively carrying out processes under these conditions.

CONSTITUTION: Eight small-sized parts 1 are held by a holder 5 also used as a jig respectively in the specified arranging direction and arranged position by inserting the tongues 2 and 3 into a small window 9 and an insertion hole 10. The held parts 1 are heat-treated to relieve residual stress, then cleaned with a solvent, degreased and freed of dust. The static elasticity of the part 1 is discharged by ion treatment, the holder is placed on a coating table, and the part is coated with a specified paint. The part is then dried along with the holder, and the part is baked and dried by a batch drier for the time set for each part. The parts are respectively marked based on a preset control program, and the product is inspected.