It is thought the man - described as being of average height, dark-skinned and athletic build - possibly followed her home.
Police have issued an appeal for anyone who may have seen anything or anyone acting suspiciously in or around the Mackinnon Terrace and Fernhill Rd intersection between 1.30 and 2.45am to contact authorities immediately.
The attacker was wearing a grey-hooded sweatshirt and spoke in a non-Kiwi accent.
The victim has undergone a medical examination and is now being supported by her partner.
Cameron urged people to check and lock doors and windows before going to sleep and if possible, install an alarm or sensor security light outside entrances.
"Police are doing all that we can to identify the person involved but we are asking for the help of the Fernhill community to find the person responsible as quickly as possible to avoid any further such attacks."
**Can you help? Contact Queenstown Police: (03) 441 1600 or CrimeStoppers anonymous on 0800 555 111.