The Australian Constitutions Act 1850, or the Australian Colonies Government Act 1850, was an act of the Parliament of the United Kingdom which was enacted to formally establish the Colony of Victoria by separating the District of Port Phillip from the Colony of New South Wales. The act provided an initial constitution for Victoria, which included a bicameral parliament and a Lieutenant-Governor as its vice-regal representative. It also altered the constitution of the Colony of New South Wales, and provided for similar constitutions to be set up in Van Diemen's Land (Tasmania) and South Australia.