Jim McColl, who took over the shipyard in 2014, told the BBC that the First Minister’s claim the yard would close without the contract for two new CalMac ferries was “a lie”.
The former SNP ally also disputed the party leader’s claim that 400 jobs were saved by the contract for the ferries.
He has previously said the contract was rushed through for political reasons in 2015 due to the SNP conference, something the Scottish Government strongly denies.
The two ships, the Glen Sannox and the unnamed hull 802 are now at least five years late and running at £150m over budget.
Ms Sturgeon and her government has come under fierce pressure around why ministers decided to award the contract to FMEL given concerns raised by ferry infrastructure owners CMAL over the lack of a full builder’s refund guarantee.
The contract has resulted in years of disagreement between Ferguson Marine, CMAL and the Scottish Government over who is responsible for the delays to the vessels.
Speaking on the BBC’s Good Morning Scotland programme, Mr McColl denied that the yard would have shut down without the contract with the loss of 400 jobs.
He said: “That’s a lie. At the time there were 150 employees, not 400.
“I think she was a bit ratted in the interview and she mixed it up with the statement that they made about saving the yard.”
The shipyard in Port Glasgow was eventually brought into public ownership in 2019.
When it was suggested to Mr McColl that calling her statement a lie was “very strong words”, he said: “Well, it’s not true”.
Mr McColl continued: “The yard had an outstanding work.
“It was still working on the ferry Katrina which wasn’t launched until 2016 and was delivered early and on budget.
“It also had additional construction work, fabrication work, so there was no danger of the yard going under at that time.
“That was a slip by the First Minister in the interview.”
Mr McColl then admitted he had made a mistake himself in an earlier interview with Good Morning Scotland.
He had initially claimed he had not signed the contract for the ferries, but documents bearing his signature were produced which showed this was not the case.
The businessman also said his company had been clear with the government from the start about the lack of a cash refund guarantee.
He said: “When we were tendering for it, you’re right that was in the tender, we made it clear we couldn’t do that.
“We were told that we could put together an alternative which we did and we put a proposal in August 26 which was not a full cash fund guarantee but it was a parent company guarantee and an insurance bond.”
It is now estimated that the two CalMac vessels will not be completed until 2023 at a cost of £250 million, more twice than the original budget.
Mr McColl, owner of Clyde Blowers Capital, sat on the SNP Scottish Government’s Council of Economic Advisers until the body was replaced in July 2021.