Miyauchi (written: 宮内) is a Japanese surname. Notable people with the surname include:
Atsushi Miyauchi (宮内 敦士, born 1969), Japanese actor and voice actor
Hiroshi Miyauchi (宮内 洋, born 1947), Japanese actor
Katsusuke Miyauchi (宮内 勝典, born 1944), Japanese writer and activist
Kōhei Miyauchi (宮内 幸平, 1929–1995), Japanese actor and voice actor
Masaru Miyauchi (宮内 優, born 1984), Japanese bobsledder
Reina Miyauchi (宮内 玲奈, born 1978), Japanese singer
Satoshi Miyauchi (宮内 聡, born 1959), Japanese footballer
Takayuki Miyauchi (宮内 タカユキ, born 1955), Japanese singer
Yoshihiko Miyauchi (宮内 義彦, born 1935), Japanese businessman
