Japan's ancient statues of Bhaisajyaguru are uniquely different from those of Korea and China not only in terms of the objects held by them, but also in the way their garments are depicted, and the way they are seated. Thus, Japan presumably established and developed iconographies of its own but little attention has ever been paid to them. This paper targets representative examples of Japan's ancient Statues of Seated Bhaisajyaguru, which date back to the 7th to 10th century, and examined their iconographic characteristics and the background to their creation. The establishment and development patterns of Japan's statues of Bhaisajyaguru iconography were also reviewed. Thus, the meaning of such iconography was studied, and the following conclusion was reached. The chief characteristics of these icons are as follows: each statue features a robe draped over the right shoulder; and the assistant is seated in the Asana style with the left foot on top of thigh. Such characteristics first appeared in the Hakuho Period. Japan's Bhaisajyaguru faith originated from Motoyakushiji Temple in the Hakuho Period. This temple and Bhaisajyaguru were important to emperors such as Tenmu, Jitou, Shomu and Koken in terms of lineage or miraculous virtue; thus, the iconographies of the Yakushiji Temple and Bhaisajyaguru greatly influenced future generations of Japanese. Meanwhile, the Soui Sutra of the Bhaisajyaguru faith, which was written around the time Yakushiji Temple was constructed, was presumably the latest translated version, i.e. the Bhaisajyaguru Sutra ( 650).