Nicola Sturgeon will call on the Chancellor to abandon "potentially catastrophic" cuts to tax credits which she says will hurt many of those most in need of help.
The First Minister will set out her case as she delivers the annual Jimmy Reid Memorial Lecture at Glasgow University on the eve of George Osborne's spending review.
Mr Osborne has already agreed to set out transitional arrangements to help people hit by tax credit cuts after facing defeat on the issue in the House of Lords, but opposition parties want him to reverse his decision.
Scottish Labour has promised to restore tax credits in Scotland when new powers over taxation and welfare are devolved to Holyrood while the SNP has also vowed to make up any shortfall.
Ms Sturgeon will say: "Tomorrow, the Chancellor of the Exchequer will announce the results of the UK Government's spending review. He has a chance - possibly a final chance - to change course on some potentially catastrophic decisions.
"For example, if all of the UK Government's proposed tax credit changes are implemented, around 200,000 families with children in Scotland stand to lose an average of approximately £3,000 a year.
"More than three-quarters of the families who receive tax credits have at least one person who works.
"The cuts are directly targeted at working people on low incomes and their children. They hurt many of the people we most need to help."
She will add: "I call again tonight on the Chancellor to reverse his decision to cut tax credits when he has the opportunity to do so tomorrow.
"If he doesn't do so, the Scottish Government will set out proposals to protect the incomes of low-paid families in our budget in December."
Ms Sturgeon will also tell her audience there was no consultation before the cuts were announced and no mention of them in the Tories' election manifesto.
"This is something which is being done to people - to working families and their children - with no opportunity for meaningful debate or discussion.
"If you reflect on the opening of Jimmy Reid's rectorial address - its evocation of 'the despair and hopelessness that pervades people who feel with justification that they have no real say in shaping or determining their own destinies' - it's hard to avoid the conclusion that UK Government policy is not tackling alienation, but breeding it."
A Treasury spokesman said: "On Wednesday, the Government will set out its plan to deliver economic security for the whole of the UK, so that we can enhance our national security, and extend opportunity to all.
"Key to this is delivering sustainable public finances and getting the deficit under control to prepare the country for any economic shocks that lie ahead.
"The Chancellor has made clear that the Government will listen about how we make a transition to a higher wage, lower tax and lower welfare economy he wants to see, and will announce his proposals at the spending review and Autumn statement.
"But the end goal is clear – this country cannot have an unlimited welfare budget that squeezes out other areas of public expenditure."