Kuniyasu was born with the name Yasugorō 安五郎 in 1794 and became a student of Utagawa Toyokuni I. He used the alternate names Ippōsai 一鳳斎 and Nishikawa Yasunobu. He was a prolific book illustrator, also specializing in beauty and actor prints, which were more angular in style than those of his teacher.