The Idaho Department of Environmental Quality is the department of the Idaho state government responsible for administration of state and federal environmental laws and regulations.

The department was established in 2000 upon the passing of amendments to the Idaho Environmental Protection and Health Act.

Prior to 2000 DEQ in Idaho was a division of the Department of Health and Welfare.

[1] [2] It is organized into five divisions: The department also exercises non-regulatory oversight over the Idaho National Laboratory.

Additional regulatory authority is vested in the Idaho Board of Environmental Quality, which, with the advice of the state attorney general, sets rules and regulations carried out by the department.