Brown, who was introduced to delegates by his wife Sarah, won applause with promises to offer more free child care, protect Britain's health service and defeat David Cameron, the opposition Conservative party leader.
"What has become clear is that Britain cannot trust the Conservatives to run the economy,'' Brown said.
"Everyone knows that I'm all in favour of apprenticeships, but let me tell you this is no time for a novice,'' Brown said, in an apparent swipe at both Cameron, and challengers in his own ranks, including David Miliband, his younger foreign secretary.
Brown emphasised that the world of today was a very different one from the one the Labour party found when they took power in 1997.
"In these uncertain times we must be, we will be, the rock of stability and fairness upon which people can stand," he said.
"I know who I am, I know what I want to do in this job. And I know the best way to deal with tough times is to face them down".
Britain's economic crisis, including a sharp drop in house prices, has led to rising disillusion among the public over the government's policies and calls within the Labour party for a new leader.
Michael Brown, a commentator for Britain's Independent newspaper, told Al Jazeera that he thought Brown's speech had not brought public confidence back but had "steadied Labour nerve".
"I don't think Labour MPs will mount a putsch against him in the next month or two, or possibly until next year. But he's not out of the long-term wood... Eventually Labour MPs will take a cold calculation.
"If by next spring the polls haven't turned, they'll say to themselves, 'maybe somebody else will give me a better a chance at holding my seat'.
"It comes down to them holding their seats and their own selfish view of their futures," he said.
Since replacing Tony Blair, the former prime minister and Labour leader, in June 2007, Brown's party has fallen to almost unprecedentedly low ratings in opinion polls, has been defeated in a series of local elections and lost control of the mayoralty in London.
Several Labour MPs have urged Brown to quit, with one junior minister resigning last week.
Many commentators predict that the Labour party will lose the next national elections, which must be called by mid-2010.