Pre-tax profit rose 50% to £10.2 million, while sales rose 5% to £56.2 million in the first six months of the year, boosted by digital revenues and its production arm.
Turnover at STV Productions doubled to £3.5 million, driven by a number of popular recommissioned TV shows, including the BBC's Antiques Road Trip, STV said.
Cheif executive Rob Woodward told the Press Association that he does not expect advertising to dry up in the wake of the EU referendum.
"The world continues as it did before," he said. "We haven't seen any advertisers change their bookings and there is no indication that will happen."
Mr Woodward said STV had managed to stay nimble by learning and growing alongside consumers, using social media and offering digital videos to keep viewers engaged once they step away from the television.
But he said the demise of linear television was not imminent.
"It's proved amazingly resilient, and in Scotland the average STV viewer continues to watch over one hour and 40 minutes of STV every day, 365 days a year, so that's pretty strong data," said Mr Woodward.
He would not speculate on the probability of Scottish independence in the wake of the Brexit vote, stressing that STV remains completely and editorially impartial on the issue.
However, he said STV has played a strong role in providing a platform for political debate, whether it be on Scottish independence, the general election or the recent Brexit vote.
The prospect of Scottish independence "is not an immediate issue" for the company, Mr Woordward added.
"Our focus is to deliver services in Scotland which are demanded by media services, and content services which are demanded by consumers."
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