Kamajiro had learned Confucianism and Sinology at Shoheizaka Gakumonjo (Shoheizaka School) and English at a private school of John Manjiro since he was a child, and at the age of nineteen he went to Hakodate, Ezochi (inhabited area of Ainu, now Hakodate City, Hokkaido) as a follower of Toshihiro HORI, who was an ongoku-bugyo (the collective name of the magistrates placed at important areas directly controlled by the government in Edo period), and took part in the exploration of Sakhalin.
釜次郎は幼少の頃から昌平坂学問所で儒学・漢学、ジョン万次郎の私塾で英語を学び、19歳で遠国奉行堀利煕の従者として蝦夷地箱館（現北海道函館市）に赴き、樺太探検に参加する。