This article is about a certain group of mountain ranges in the Northern Interior of British Columbia and southern Yukon, as defined by a government-commissioned geographic study which forms the basis for the provincial gazette. For other mountain ranges of the British Columbia Interior and southern Yukon see Rocky Mountains, Columbia Mountains, Cascade Mountains and the subranges listed on the Interior Plateau article. For the region of British Columbia known as "The Interior", see British Columbia Interior.

The Interior Mountains, also called the Northern Interior Mountains and Interior Ranges, are the semi-official names for a huge area that comprises much of the northern two thirds of the Canadian province of British Columbia and a large area of southern Yukon. There are four main groupings, the Skeena, Cassiar and Omineca Mountains to the north of the Interior Plateau between the Coast Mountains to the west and the Rocky Mountains to the east, and the Hazelton Mountains along the Interior Plateau's northwestern flank against the Coast Mountains, extending from the Bulkley Ranges south to the Bella Coola River. Included within the Interior Mountains system is the Stikine Plateau, which contains a number of sub-plateaus and various mountain ranges and is located west of the Cassiars, north of the Skeenas, and to the east of the Boundary Ranges of the Coast Mountains. Most of the thousands of summits in the Interior Mountains are unnamed, and they are mostly uninhabited and undeveloped.