Ashiya, city, southeastern Hyōgo ken (prefecture), west-central Honshu, Japan. It is surrounded by the Rokkō Mountains and faces Ōsaka Bay.
Ashiya is located on railway lines and highways between Kōbe (west) and Ōsaka (east), and it has been known for its beauty since the Heian period (794–1185), when court nobles and men of letters lived there. After the establishment of the first railway line to it in 1905, the city became a renowned residential area. One-third of its central area was destroyed during World War II, and it was also heavily damaged in 1995 by a major earthquake in the region; both times it was rebuilt. It remains one of the wealthiest cities in Japan. Pop. (2005) 90,590; (2010) 93,238.