Nationalists and Labour MSPs united to reject benefit changes linked to Iain Duncan Smith’s shake-up.
Among the more controversial measures is the capping of housing benefit and the introduction of a universal benefit.
It is the first time in its 12-year history that the Scottish Parliament has voted against a special motion allowingWestminsterto act on devolved matters.
The largely symbolic move followed an appeal by Health Secretary Nicola Sturgeon for MSPs to take a stand.
She conceded it will not stop the Welfare Reform Bill being passed atWestminster. But it will lead to Holyrood agreeing its own laws on areas in devolved issues such as free school meals and the blue badge scheme for disabled drivers.
The largely symbolic move followed an appeal by Health Secretary Nicola Sturgeon for MSPs to take a stand
Labour backed the SNP’s call to refuse the necessary Legislative Consent Motion (LCM) on part of the Bill, voting to reject it by 100 votes in favour to 18 against.
But the move was criticised by Tory and Liberal Democrat MSPs who defended their Coalition colleagues south of the Border.
Scottish Tory health spokesman Jackson Carlaw said the SNP and Labour were “grandstanding”.
He said: “Nothing done today will alter the course of the UK Welfare Reform Bill, regardless of the SNP’s rhetoric.
What the SNP have done is opportunistic, pointless and potentially reckless. The SNP and Labour joined together today, not to change the substance of the proposed welfare reforms, but through their action to raise the prospect of delays in the most vulnerable people inScotlandaccessing these new benefits.”
Lib Dem MSP Liam McArthur said: “At best, it seems to be a gesture, but one with potentially serious consequences.”
The UK Government has dismissed criticism that it is targeting the disabled and the vulnerable in the shake-up. It has proposed moving to a single universal credit from 2013.
The Bill replaces child tax credit, working tax credit, housing benefit and income support, among others.
Ms Sturgeon earlier told MSPs she supports efforts to simplify the benefits system but claimed measures put forward by Work and Pensions Secretary Mr Duncan Smith amount to cost-cutting.
She said benefits receipts inScotlandwould be reduced by £2.5billion by 2015, with £1billion coming from the disabled and their families.
Ms Sturgeon said: “This will be the first refusal of legislative consent in the lifetime of this Parliament.
“It is right that we stand up for the most vulnerable in our society.”
A Department for Work and Pensions spokeswoman said: “These reforms will end the cycle of generations of Scots living a life on benefits. When one in five Scottish households is workless, something fundamental needs to change.”