Alex Salmond said much had been achieved north of the border since the advent of devolution, but much more could be done with the powers that full independence would bring.
Mr Salmond said: "With the partial independence the Scottish Parliament has in health, education, justice, business support and social services, we have achieved much - and with the full measure of independence we get by voting Yes, we will achieve much more for Scotland."
The conference in Inverness comes just two days after he said that voters in Scotland will decide the country's future in an independence referendum to be held on September 18 2014.
Nationalists will use the gathering to set out their arguments for leaving the UK, with Mr Salmond stating: "Conference will set out the 'why of independence' to the people - what won't happen in an independent Scotland will be getting dragged into illegal wars, having Trident nuclear weapons dumped on the Clyde for another 50 years, or the imposition of bedroom taxes.
"And what will happen will be the mobilisation of the human and natural resources of Scotland to build a prosperous economy and just society."
Mr Salmond said that in the six years the SNP has been in power in Scotland it had "taken trust in the Scottish Government to a high of 71% - four times more than trust Westminster".
The First Minister used his conference speech this afternoon to argue Scotland would be better off economically if the country was independent.
He also sought to contrast policies north of the border with those in England, highlighting the provision of free personal care for the elderly, the increase in police numbers since the SNP came to power and the abolition of university tuition fees for Scottish students.
Meanwhile, his deputy opened the event by saying the next 18 months will be the most exciting in Scotland's history. Deputy First Minister Nicola Sturgeon declared the crucial ballot would be Scotland's "date with destiny".
She told activists: "The next 18 months will be the most exciting in our history. Let's make sure we seize that opportunity, let's make sure that we win the referendum for ourselves and future generations."
She added: "Over the next 543 days we have the opportunity to persuade people right across our country not just that we can be independent, but that we must be independent, that Scotland would be better off independent."
She held up a copy of the Scottish Independence Referendum Bill published on Thursday, which she said would "give the people of Scotland the right to choose our own future, the right to choose independence".
She read out part of the Bill, which states: "A referendum is to be held in Scotland on a question about the independence of Scotland.
"The question is: Should Scotland be an independent country?"
Ms Sturgeon continued: "I joined this party when I was 16 years old. When I joined the SNP I of course imagined Scotland being independent, but I never ever imagined putting my signature on the Bill that will help make independence a reality.
"The Bill will set September 18 2014 as the date, Scotland's date with destiny."
She said the SNP had "shown beyond any doubt that Scotland can afford to be independent" as she hit out at "disgraceful welfare cuts being imposed on Scotland by a Tory government we didn't vote for".
Ms Sturgeon argued: "Why should Scotland be independent? Because that way we will always get the government we vote for.
"Because if we are independent, when we are independent, we will use Scotland's resources to build the better country that we want to live in."
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