A chain component part has a first coating film formed on an iron base material using a water-based rust preventive paint containing a water-based rust preventive pigment containing a nitrate and having good storing stability. Since zinc is eluted earlier, generation of red rust caused by iron is suppressed, and thus durability is improved. A roller chain (10) includes a zinc-iron alloy ground layer (24) formed on an iron base material (22) by impact zinc plating, a first coating film (26) formed using the water-based rust preventive paint, and a second coating film (28) formed using a water-based top coat paint containing a water-based pigment and a water-soluble or hydrolyzable silane coupling agent containing an amino group.