Police said a man armed with a knife entered Henry's Liquor Store in Shotover Street and demanded cash at about 6.50pm.
After obtaining the cash, the man, still armed with the knife, ran from the store and took a motor vehicle from a member of the public.
The offender and another person then drove off in the stolen vehicle.
Police, along with members of the public, followed the vehicle to the Mooney Road area of Queenstown where one of the people in the vehicle was arrested.
The second person was arrested shortly afterwards.
Residents in the Mooney Road and Dalefield Road areas of Queenstown are asked to ensure their vehicles and houses are secure and that they leave outside lights on.
They are also asked to report any suspicious activity.
Witnesses say at least five customers were inside the Henry's liquor store in Shotover Street about 6.50pm when a man walked behind the counter, threatened a store assistant with a knife and took cash from the till.
Max Gooch, of Sydney, said the man had blood on his face and "didn't say a word" during the robbery.
"I went to the counter to pay, and the guy behind the counter gave me a really weird look."
Mr Gooch "grabbed" his girlfriend and the couple - who only arrived in the resort this morning - quickly left the store.
"The guy walked off really calmly to the corner. He got some money - I don't know how much."
Queenstown resident Douglas Hogg said he noticed something was amiss just after leaving the store.
"I looked back and the guy walked behind the counter. I saw him pull something out and the guy at the counter opened the till and stepped back.
"The guy put his hands in the till and walked out."
The whole incident lasted about about 30 seconds, Mr Hogg said.
