The race, which usually begins on a Saturday, will begin a day early in 2014 to accommodate an extra rest day during which the teams will transfer from Ireland to Italy for the rest of the race.
The change of date for the Grande Partenza was officially approved by the UCI this week.
Belfast will also hold stage two of the race before it moves on to Dublin on the Sunday and then to Italy before the fourth stage on the Tuesday.
Giro d'Italia director Michele Acquarone apologised to spectators forced to change travel and accommodation arrangements to watch the opening stage of the race.
"I apologise with fans who already plan their trip to Ireland. We have to change our plans and we have troubles too," he said via Twitter.
Stage one will begin in Belfast’s Titanic Quarter before finishing in the City Hall area while stage two will also start and finish in Belfast.
Sunday’s stage three will begin at The Mall in Armagh before crossing the border on the way to a Dublin city centre finish.
"I have been advised of the earlier start date for the Giro d'Italia in Belfast, which moves forward by one day to the 9th May, and am confident that this will not cause any difficulties," said Northern Ireland Tourism Minister Arlene Foster.
"Everyone in Northern Ireland is looking forward to welcoming this hugely exciting competition to our shores next year and to embracing the passion, colour and atmosphere that comes with the Grande Partenza."