A manufacturing method of a coil component comprising the steps of: preparing a coil assembly body in which a coil is attached on a magnetic core and a mold body which is formed with a cavity portion in the inside thereof and which includes at least one opening portion, putting a viscous admixture including magnetic powders and thermosetting resin and the coil assembly body in the cavity portion, pushing the put-in viscous admixture in the mold body, and thermally-curing the pushed-in viscous admixture and forming a magnetic exterior body which covers the coil assembly body.