The Mittagong Formation is a sedimentary rock unit in the Sydney Basin in eastern Australia.

[2] Near Town Hall railway station, the formation is 8 metres thick.

In northern Sydney it can be seen in several areas, such as West Pymble[3] and Mount Ku-ring-gai.

[4] This rock formation is associated with the critically endangered Sydney Turpentine-Ironbark Forest.

This article about a specific Australian geological feature is a stub.