The Macquarie Marshes Nature Reserve is located in the Macquarie Marshes.

The Macquarie Marshes are a region along the lower Macquarie River in northwestern New South Wales about 600 km northwest of Sydney. The marshes are created by irregular flooding of the flat lands along the river and are an important habitat for breeding birds.

The nature reserve covers only a small part of the marsh area. The rest of it is private agricultural holdings.

The frequency and extent of the flooding required to sustain the marshes is threatened by increasing extraction of water from the Macquarie River for crop irrigation upstream from the marshes.