The Department of Environment and Conservation came into being through the amalgamation of the Department of Environment and the Department of Conservation and Land Management.

The Department had the lead responsibility for protecting and conserving the State's environment. This included managing the State's national parks, marine parks, conservation parks, State forests and timber reserves, nature reserves, marine nature reserves and marine management areas. Its key responsibilities included broad roles in conserving biodiversity, the development of environmental protection polices and responding to pollution incidents.

On 1 July 2013 the Department of Environment and Conservation was separated into two agencies: the Department of Parks and Wildlife and the Department of Environmental Regulation.