Junkei (順慶) is a Bizen smith active no later than the mid-Kamakura period, now firmly identified as an individual distinct from Osafune Nagamitsu. Since the Edo period, Junkei was regarded as the Buddhist name (hogo) of Nagamitsu, and two competing views persisted: that Junkei and Nagamitsu were the same individual, and that they were different individuals. Today, on the basis of workmanship as well as the style of the calligraphy and the manner of the chisel work in the signature, the view that they were different individuals has been adopted. The NBTHK further considers that Junkei was not a smith of the Osafune group, and that his dating should be placed earlier — his workmanship being unequivocally that of Ko-Bizen.

Junkei's forging is an itame-hada mixed with o-itame and mokume; the grain characteristically stands out (hada-datsu), and midare-utsuri appears in the ji. The hamon varies between a suguha-based temper mixed with gunome and ko-midare, and a choji mixed with gunome showing abundant ashi and yo. A defining trait is notably strong nie; among works attributed to him, they generally differ from Nagamitsu in being nie-deki. Kinsuji and sunagashi appear, and the nioi can be deep. The boshi tends toward sugu, turning back in ko-maru. Overall, the work presents an archaic (kocho) character consistent with Ko-Bizen.

The recognition of Junkei as a separate, pre-Osafune smith represents a significant scholarly correction. Honma Junji stated that when he served in the Ministry of Education, he deliberately recognized Junkei's work as Ko-Bizen. Signed tachi by Junkei are precious; one published example appears in the Tsuchiya Oshigata, and others are recorded in the Kozan Oshigata, Nihonto Zuikan, and Shinpan Nihonto Koza. His oeuvre provides an important bridge between the Ko-Bizen tradition and the later Osafune mainstream, preserving the older, nie-dominant aesthetic that would give way to the nioi-based refinement of Nagamitsu and his successors.