The newly elected party leader said that unlike her predecessors, she would not just listen but act to change Scottish Labour by offering new policies and rebuilding the front bench team.
Ms Dugdale said Labour had to break its losing streak at May’s elections to the Scottish Parliament.
She told activists in Brighton: “Scotland needs a strong Labour Party and a strong opposition to the Scottish Government.
“Because for eight years, the SNP Government have had the chance to change our schools, change our hospitals, change our country for the better. But the truth is they haven’t.”
The Edinburgh and Lothians MSP vowed to campaign for better education ahead of the Holyrood polls, and added warnings of an NHS “creaking at the seams”.
Ms Dugdale said: “In Scotland, we have a Government that is presiding over falling standards in our schools and hospitals.
“A Government who have governing as a second priority, opting instead to carry on an argument that the vast majority of Scots don’t want to have.
“And this has consequences. It means difficult decisions delayed, progressive choices dismissed and, tragically, a lack of political will to use the powers we have in the Scottish Parliament.”
The SNP said Ms Dugdale’s speech showed nothing had changed for Scottish Labour.
MSP Linda Fabiani said: “Kezia Dugdale’s speech today was yet more of the same tired, old negative lines that Labour has been using for the last eight years in Scotland - and is indicative of a party that is all out of ideas.
“Today we heard more of the same recycled promises about how Labour would change - the problem for Ms Dugdale is that these are the same promises we’ve heard from Wendy Alexander, Iain Gray, Johann Lamont and Jim Murphy - and people in Scotland are simply fed up hearing it.”
Ms Fabiani added: “The fact is that people in Scotland aren’t going to be quick to forgive or forget the way Labour stood shoulder to shoulder with the Tories during the referendum. And with John McDonnell pledged to back George Osborne’s fiscal plans, people across the country will be wondering whether Labour is capable of changing at all.”
Shadow Scotland secretary Ian Murray joked he was the “last man standing” as Labour’s last Scottish MP in Westminster.
He promised to push for further devolution in the Scotland Bill.
He told conference: “We need the Tories to stay true to the spirit and letter of the Smith Agreement. To ensure that we have the power in Scotland to create the welfare system we want, with no threat of interference from (Work and Pensions Secretary) Iain Duncan Smith.
“So if the Prime Minister and the Scottish Secretary are serious about powers for Scotland, I say this to them today: Accept Labour’s changes. Don’t break your promises. And don’t deny the will of people across Scotland.
“This Bill should herald a new era for the Scottish Parliament.”
Earlier, Labour leader Jeremy Corbyn accused the SNP of wearing an “anti-austerity badge” while pursuing policies which continue it, or could make it worse in future.
Mr Corbyn, who will be in Scotland next Thursday, said his message is “flags don’t build houses”.
The Labour leader was speaking on BBC One’s The Andrew Marr Show as the party’s conference got under way in Brighton.
SNP deputy leader Stewart Hosie dismissed his comments as “the same old lines we have heard for years”.