Kiyonori signed as Fujiwara Kiyonori and worked within the Bizen Yoshii school, a lineage traditionally said to have begun with Tamenori in the late Kamakura period. While works traceable to the Kamakura era are exceedingly rare, pieces produced through the Nanbokucho period are classified as Ko-Yoshii, and those of the Muromachi period simply as Yoshii. Unlike other Bizen lineages that were consolidated into Osafune during the Muromachi period, the Yoshii school alone continued independently, maintaining a distinctive style. Kiyonori is transmitted as a son of Yoshinori and was active from the Kakitsu through Hotoku eras, with dated works spanning 1442 to 1451.

The hallmark of Kiyonori's work lies in a hamon of ko-gunome running in a regular, continuous sequence, a defining trait of the Yoshii school that he consistently exemplifies across both tachi and wakizashi. His kitae is typically a tight itame-hada mixed with mokume, showing fine ji-nie densely applied, and bearing the school's characteristic midare-utsuri -- an effect in which the form of the hamon itself appears projected as a shadow into the ji. The boshi enters in a corresponding midare-komi manner, and the signature makes frequent use of saka-tagane (reverse chisel strokes). In several examples the nioiguchi is soft, with ko-nie and sunagashi, imparting what the NBTHK has described as an archaic flavor approaching the artistic range of Ko-Yoshii. His hira-zukuri wakizashi demonstrate a suguha mixed with small gunome, and one such piece preserves a finely executed ukibori of shin no kurikara -- horimono being extremely rare in Yoshii school production.

Kiyonori's dated works are of high documentary value for the study of the Yoshii school, and several have been praised for their thick kasane, sound kenzen condition, and strong sense of hand. That his work at times approaches Ko-Yoshii caliber within a Muromachi-period framework attests to the quality of craftsmanship he sustained.