The Department of Biological Sciences has been in existence for more than 75 years. In the early years biologists at the University of North Texas were part of a Division of Science that also included what are now the Departments of Physics and Chemistry. Master's degrees in biology were first offered in 1936. The graduate school was established in 1946 as part of a major reorganization of the institution. In 1968, the Coordinating Board of Colleges and Universities confirmed the university's mission to offer doctoral programs in the basic arts and sciences, teacher education, business administration, and the fine arts, as well as cooperative doctoral programs in other fields. Biological Sciences obtained authorization to offer a doctoral degree in biology at this time.

In 1968 UNT and Biological Sciences became members of the newly established Federation of North Texas Area Universities. With the guidance of the Texas Higher Education Coordinating Board, the Federation was formed from a sharing of resources between UNT, Texas Woman's University in Denton, and East Texas State University at Commerce (now Texas A&M University Commerce). As part of the Federation, Biological Sciences started offering masters and doctoral degree programs in molecular biology. Most recently, Biological Sciences has gained permission to offer graduate degrees in environmental sciences and has expanded the molecular biology degrees to include biochemistry and molecular biology.

The recommendation by the Select Committee on Higher Education in 1985 that the university be designated "an emerging national research university" bolstered the aspirations of the faculty toward research and scholarship. Graduate education and research are two commingled parts of the same enterprise in any major academic institution.

Faculty in the department are promoted and tenured based upon a critical review of performance of teaching, research or other scholarly or creative activities, and service to the department, university and profession as detailed in the Departmental Criteria for Promotion and Tenure.