The Upper Macquarie County Council was originally constituted by proclamation on 18 February 1949. The Local Government Act 1993 operated to continue the county council as if it had been constituted under Section 387 with an area of operations the same as its former county district.

The constituent councils of Upper Macquarie County Council are –

Bathurst Regional Council

Lithgow City Council

Blayney Shire Council

Oberon Council

Each constituent council elects 2 members of the County Council.

The chairperson of the County Council is elected by the members of the County Council from among the members.