Miyaji is a Japanese surname that may refer to Atsuko Miyaji, Japanese cryptographer and number theorist Katsuhiko Miyaji (born 1971), Japanese baseball outfielder Kazuaki Miyaji (born 1940), Japanese politician Mao Miyaji (born 1984), Japanese actress Masayuki Miyaji (born 1976), Japanese anime director and supervisor Takeshi Miyaji (1965–2011), Japanese video game developer Toshio Miyaji, Japanese football player Yoshihisa Miyaji (born 1973), Japanese weightlifter Yōsuke Miyaji (born 1987), Japanese football player