The Department of Environment and Natural Resources Region 6 (DENR 6) was operationalized by the creation of a Regional Office in Iloilo City thru Executive Order No. 192 issued on June 10, 1987 by President Corazon Aquino.   Under said order, DENR 6 comprised of five (5) technical services: the forestry, lands, environment and protected areas, mines and geo-sciences, and research.  As support, finance, legal, administrative, and planning services were also provided. For every province, a provincial environment and natural resources office was created to oversee and coordinate the implementation of DENR programs and projects within its administrative jurisdiction.  Simultaneous with the creation of provincial environment and natural resources offices, community environment and natural resources offices were also created in selected cities and municipalities which are centrally located to most if not all of the projects.  This is to provide more accessibility to the target clienteles and beneficiaries.

With the passage of Republic Act No. 7942 in 1995, the Mines and Geo-sciences Bureau became an attached bureau under the Office of the Secretary with the same status as the DENR Regional Office.  The Environmental Management Bureau followed suit in June 23, 1999 when the same also became an attached bureau by virtue of Republic Act 8749, separating it from the Protected Areas and Wildlife Bureau.