is a city located in Sorachi Subprefecture, Hokkaido, Japan.
As of 2023, the city has an estimated population of 19,242, and the density of 69.3 persons per km<sup>2</sup>. The total area is 277.69 km<sup>2</sup>.
The name Bibai is derived from Ainu word "pipa o i", meaning "Place (swamp) with many cockscomb pearl mussels".
At its peak, Bibai was a coal town that produced over a million tons annually. However, ever since the mine was closed in 1972, the city has suffered a slowly declining population.
The Ishikari River flows to the west of Bibai. The Bibai Dam was built on the Bibai River, a tributary of the Ishikari River.
Lake Miyajima was registered as a wetland under the Ramsar Convention in 2002.
Per Japanese census data, the population of Bibai has declined by more than half over the past half-century.
Hakodate Main Line Minami-Bibai Branch Line used to run from Bibai to Minami-Bibai.
Straight line section of Route 12 is the longest in Japan.
Bibai's mascots are . He is a greater white-fronted goose. He was unveiled in 1986. is Mami-chan's assistant who is a yakitori.