Harumitsu (治光) was a swordsmith of , working at in Province across the Eishō, Daiei, and Kyōroku eras. He was the son of Jirōzaemon-no-jō Katsumitsu, one of the most skillful masters, and himself bore the title Jirōbei-no-jō; tradition further records that he was the father of Jūrōzaemon-no-jō Shunkō (春光). The note that several smiths shared the Harumitsu name, bearing such zokumyō as Saemon-no-jō, Gorōzaemon-no-jō, Magojūrō, and Jirōzaemon-no-jō, with their combined activity extending from Bunmei through Bunroku. A surviving joint signature with his father Katsumitsu, dated Daiei 7, stands as valuable documentary evidence of the father-and-son pairing.
His characteristic shows the period clearly: with pronounced , often a wide and thick , producing a bold presence, though slender, -like figures also appear. The is consistently a well-forged, densely packed or , with adhering thickly and entering. His signature is the hallmark , in which the split and form a compound () , mixed with , , , and ; and run through the hardened area. He also worked in a broad with shallow , and produced large of magnificent figure with broadened head and powerful curvature.
The regards his finest blades as displaying "an outstanding level of workmanship among works," counting them among his . His range — from disciplined preserving an Ōei- manner, to flamboyantly tempered broad blades — reveals the considered intention behind his style and his standing within the late tradition.