Soon-ja, also spelled Sun-ja, is a Korean female given name.
According to South Korean government data it was the seventh-most popular name for baby girls in 1940.
[1] The same characters correspond to a number of Japanese female given names, including the on'yomi reading Junko and the kun'yomi readings Ayako, Masako, Michiko, Nobuko, and Yoshiko.
[2] It is one of a number of Japanese-style names ending in "ja", like Young-ja and Jeong-ja, that were popular when Korea was under Japanese rule, but declined in popularity afterwards.
[3] By 1950 there were no names ending in "ja" in the top ten.