Derek Mackay has been accused of spending millions intended to protect Scotland from a no-deal Brexit on other things.
Labour claimed the Finance Secretary had spent £10 million of a £37.3 million Brexit pot on items that were not directly related to EU withdrawal.
The £37.3 million was Scotland’s share of the £1.5 billion Brexit preparation funds allocated to UK departments in 2018/19 and 2019/20.
Labour finance spokeswoman Jackie Baillie made the claims after Mr Mackay told her in a Holyrood answer that £27 million had been allocated to specific Brexit-related activity in the Scottish Government and its agencies.
He added that the remaining £10 million was spent on Scottish Government portfolios such as health, education and the environment departments as part of the 2018-19 Scottish Budget.
Ms Baillie said: “The SNP’s decision to blow £10 million of no deal Brexit funding has left Scottish businesses and the jobs they support at risk.
“Derek Mackay is doubling down on the Tories’ economic incompetence with this decision.
“A no deal Brexit will never be a credible option, but neither is blowing preparation funding which could shield Scottish businesses from the worst excesses of a new Tory Prime Minister.”
Mr Mackay’s spokesman said: “Over the last few weeks Labour have accused the SNP Government of overspending our budget, then they criticised us for underspending it and now they’re criticising us for not underspending enough.
“The only consistency in Labour’s position is that they don’t have any idea how public finances work.
“If Labour really want to prevent the potentially catastrophic consequences of a no deal Brexit then, instead of manufacturing silly grievances such as this, they would be joining with us in opposing Brexit being imposed on Scotland against our wishes.”