The suspension, which starts on March 9, comes after the hotel's sixth breach of the Sale and Supply of Alcohol Act since 2012.
Four have involved the sale of alcohol to minors, and led to suspensions of three days in 2013, 24 hours in 2016 and two days in December.
In his decision, Judge Kevin Kelly, of the Alcohol Regulatory and Licensing Authority, said another significant breach would "almost certainly" result in the hotel's on-licence being cancelled.
Queenstown police applied for the suspension after a controlled purchase operation on September 15 last year, in which a 17-year-old volunteer was served beer.
Contrary to the submissions of the licensee's counsel, the premises were "problem premises", Judge Kelly said.
As well as the frequent breaches, police had been confronted by patrons when they entered the bar after the September operation, with one man standing in the officers' way.
When the two officers later went to leave, the same man and a friend put their stools in the way and told them to "go around".
When told to move the stools, the man had stood a "couple of inches" from the officer's face and asked him `Do you want to take all that gear off and go outside?"'
When the man was involved in an assault in the township later that night, he told police he had been drinking at the hotel all evening.
In his evidence, the hotel's general manager, Peter Whittaker, said he was "very disappointed" by the actions of the two staff involved.
It was "notoriously difficult" to recruit long-term staff because of the area's transient population and cost of accommodation, he said.
However, Judge Kelly said Mr Whittaker's solution of rotating senior staff from other premises in Christchurch was neither "sustainable or robust".
He was also unconvinced by his claim that he was working to improve staff training, or that changes had been made to the hotel's processes since it failed another controlled purchase operation last June.
