Melonba is a suburb of Blacktown, in the state of New South Wales, Australia.

Melonba is located approximately 51 kilometres (32 mi) north-west of the Sydney CBD in the local government area of Blacktown.

Melonba is situated in the Darug traditional Aboriginal country.

Prior to the suburb's creation, the area was part of Marsden Park.

[3] The origin of the suburb name is from the Dharug Aboriginal language meaning a type of wattle found in the area.