The property at Inshriach House, an Edwardian country house on an estate near Aviemore, is now in the running for the overall prize.
The shed's facilities are made available to guests at the house, and not open to the wider public.
The overall winner will be announced on Sunday.
Walter Micklethwait, who owns Inshriach House, built the shed with help from his girlfriend Lizzy Westman.
Until recently the property had a "house sheep", an orphaned lamb called Dash who shared a bed with Monty, a dog.
Dash has a new home in a nearby field.
Mr Micklethwait said: "The pub category is apparently the most hotly contested each year.
"I was up against Keith the Pirate from Croydon whose Caribbean themed pub was full of coconuts and parrots and has a drawbridge, Simon's nightclub in a shed and Michael Jelley's biker pub, an amazing warren of bike and booze paraphernalia.
"Perhaps the nature of our business - hospitality and gin - gave us an advantage with the public vote."
He added: "I just saw entering the competition as a laugh and a way of spreading the word about Crossbill Gin.
"What I hadn't really anticipated was what a brilliant bunch of people would be involved, some properly talented craftsmen and true eccentrics - totally unpretentious, uncompetitive and full of brilliant ideas."
A wooden building in the Highlands with a gin distillery has won the pub category of Channel 4's Amazing Spaces Shed of the Year competition.