The unseeded Australian pair of Barty and Dellacqua had a dream run making it all the way to the doubles final and even though they were able to sneak a set off the Italian pair, Errani and Vinci proved too strong in the end as the world's No. 1 pairing won 6-2, 3-6, 6-2.
The Italian pair cruised through the opening set winning it 6-2 after comfortably leading early 4-1. They then led the second set 2-1 also after breaking Dellacqua's serve, but the Australians hit back to end up winning the set 6-3, winning five of the last six games to do so.
However, after the Aussie pair got an early break in the third set, the Italians steadied to win the last four games for the loss of just six points to win the tournament.
In the end, it was the consistency of the Italians' game that saw them prevail as they got 78 per cent of first serves in to the Australians' 57 while also hitting only 22 unforced errors to 42.
Barty and Dellacqua had a terrific tournament to make it to the final as they became the first Australian duo to make an Australian Open women's doubles final since Dianne Fromholtz Balestrat and Helen Gourlay Cawley were victorious in 1977.
The Australians beat some well-credentialed teams along the way to make the final including the third-seeds Maria Kirilenko and Lisa Raymond, and 14th seeds Natalie Grandin and Vladimira Uhlirova.
Teenager Barty completed the biggest week of her career to date and Dellacqua came close to replicating her mixed doubles US French Open win with American Scott Lipsky.
However, the experience and familiarity that Errani and Vinci have from playing one another told in the end.
Even though the Italian duo are fine singles players in their own right with Errani ranked No. 7 in the world and Vinci No. 16, the pair have now claimed three doubles crowns together following wins at the Australian Open and Roland Garros in 2012.
Dellacqua now hopes to team together with the 16-year-old Barty for many Grand Slam tournaments to come as they look to go one better.
"I'd like to congratulate Roberta and Sara on a great final today. They've had a great tournament and had some really tough matches, and got through, and played really well today so congratulations," Dellacqua said.
"We've had amazing support these last few weeks and it's been such an exciting time. I also want to thank my good friend Ash Barty. She is 10 years younger than me, but she makes me feel young and we have such a blast on the court, and have had such an exciting two weeks.
"I look forward to many more doubles tournaments with her and hopefully lifting up the winner's trophy with her one day."
Vinci understandably was delighted in her third Grand Slam win alongside Errani, but knows it disappointed the home crowd.
"Maybe everyone here was hoping for a different winner tonight, I know, but I would like to say congrats to Ashleigh and Casey for playing unbelievable doubles today," Vinci said.
"I have to say thank you to Sara for playing with me and thank you to our team. Thank you also to Francesca (Schiavone) and all our fans. This is a special moment for us."
Earlier on Friday, Australians Jarmila Gajdosova and Matthew Ebden booked a place in Sunday's mixed doubles final with a 7-5 7-6 (5) semi-final win over Kazakhstan's Yaroslava Shvedova and Uzbekistan's Denis Istomin.
They will play Czech pair Lucie Hradecka and Frantisek Cermak in the final.