The Idaho Museum of Natural History is home to collections in Anthropology, Earth Sciences, and Life Sciences. The Museum also maintains an archive which documents its history as well as the history of the collections. Researchers pursue scholarly study of the collections and publish their findings in peer-reviewed and museum-sponsored publications. Exhibitions emphasize the collections and mission of the Museum, and include permanent and special offerings. Educational classes for children, families, and adults provide more in-depth exploration of the natural history of Idaho.

The Idaho Museum of Natural History actively nurtures an understanding of and delight in Idaho's natural and cultural heritage. As the official state museum of natural history, it acquires, preserves, studies, interprets and displays natural and cultural objects for Idaho residents, visitors and the world's community of students and scholars. The Museum also supports and encourages Idaho's other museums through mentoring and training in sound museological practices.

The Idaho Museum of Natural History was founded in 1934 in Pocatello as the Historical Museum at the Southern Branch of the University of Idaho, as Idaho State University was then called. The Museum was established by a group of professors in an effort to collect, preserve, and display the region's natural and cultural heritage.

The earliest collections, consisting of about 5,000 objects, were primarily anthropological, archaeological and historical artifacts largely donated by the Pocatello Chamber of Commerce and faculty and supporters of the Southern Branch. The biological collections were developed by faculty in the Biological Sciences Department at approximately the same time. The Museum was governed by a 17-member Historical Museum Committee until the mid-1950's when it was renamed the Idaho State College Museum and its first full-time director was appointed. In 1963, Idaho State College became Idaho State University, and the Museum changed its name to the Idaho State University Museum.

For many years, the Museum's holdings were strewn about the ISU campus in a variety of buildings. In 1976, Museum offices, exhibits and collections finally found a permanent home in the old library building, now known as the Museum Building. In 1977, the museum reoriented its mission to focus on natural history and the Ray J. Davis Herbarium and zoological collections were formally transferred from the ISU Department of Biological Sciences. Its historical collections were handed over to the Idaho State Historical Society, the Bannock County Historical Society, and the Idaho State University Library.

Also at this time, Museum and university officials worked at the state level to gain recognition for the Museum. In May 1977, the Idaho State Board of Education adopted a resolution requesting that Governor John Evans designate the Idaho State University Museum as the Idaho Museum of Natural History (IMNH); he signed this proclamation on July 1, 1977. In 1986, the Idaho State Legislature confirmed the governor's proclamation by enacting legislation that formally designated the Museum as the official state museum of natural history (Idaho Statute 33-3012).

The IMNH now exists as a Special Program of Public Service (with separate line-item funding) of the Idaho State Board of Education, with Idaho State University providing additional support, advocacy and supervision. Currently the Museum holds and cares for over 500,000 natural and cultural objects in its collections areas located on the first two floors of the Museum building.