Toyama Prefecture (富山県, Toyama-ken^?) is a prefecture of Japan located in the Hokuriku region on Honshu island. The capital is the city of Toyama.

Toyama is the leading industrial prefecture on the Toyama Bay Japan Sea coast, and has the industrial advantage of cheap electricity due to abundant water resources from the Kurabo Dam. It also contains East Asia’s only glaciers outside Russia, which have been recognised as such only very recently.

Historically, Toyama Prefecture was Etchū Province. Following the abolition of the han system in 1871, Etchū Province was renamed Niikawa Prefecture, but Imizu District was given to Nanao Prefecture. In 1872 Imizu District was returned by the new Ishikawa Prefecture.

In 1876 Niikawa Prefecture merged into Ishikawa Prefecture but the merger was void in 1881 and the area was reestablished as Toyama Prefecture.

The Itai-itai disease occurred in Toyama around 1950.

Toyama Prefecture is bordered by Ishikawa Prefecture to the west, Niigata to the northeast, Nagano to the southeast, Gifu to the south and Sea of Japan to the north.