Alessandro Del Piero, almost certainly playing his last home game for Juventus at the age of 37, celebrated with a goal as the Serie A champions beat Atalanta 3-1 on Sunday to finish their campaign unbeaten.
Udinese clinched a place in the playoff round of next season's Champions League qualifying tournament by winning 2-0 at Catania to finish third, leaving Lazio, Napoli and Inter Milan to contemplate the Europa League.
Antonio Di Natale, included in Italy's provisional squad for Euro 2012, opened the scoring for Udinese with his 23rd league goal of the season.
The 38-year-old Filippo Inzaghi, playing his last league game for runners-up AC Milan after 11 seasons, scored the winner in a 2-1 victory over relegated Novara.
Juventus became only the second team to win Serie A without losing a game after Fabio Capello's AC Milan in 1991-92 and the first to achieve the feat in a 38-match season.
Del Piero curled the ball in from the edge of the penalty area in the 28th minute after Luca Marrone had fired the opener for Juve who clinched the title last week.
An own goal by Stephan Lichtsteiner put a slight dampener on Juve's celebrations in the 83rd minute before defender Andrea Barzagli converted a stoppage-time penalty.
Barzagli had come on just one minute earlier following an injury to Giorgio Chiellini and became the 20th Juventus player to score a league goal this season.
"We've had a fantastic championship season, crowning it with the Scudetto and a record which will go down in history," said Juventus coach Antonio Conte. "Others can only try and equal our feat."
Club president Andrea Agnelli said last year that Del Piero's contract would not be renewed when it expires at the end of the season and seems unlikely to backtrack.
Juventus finished with 84 points, four ahead of Milan, with the two teams taking Italy's places in the group stage of the Champions League next season.
Udinese, who had needed a draw to clinch third place, left nothing to chance with a win in Sicily.
Italy has lost a place in the competition after Serie A slipped below Germany's Bundesliga in UEFA's ranking of national leagues.
Lazio took fourth place despite going behind to Inter when Diego Milito scored from a penalty, the Argentine's 24th Serie A goal of the season, on the stroke of halftime.
Parma beat Bologna 1-0 for a club record seventh successive win to finish with 56 points.
Lecce joined already relegated Novara and Cesena in Serie B next season after losing 1-0 at Chievo.
Photograph: Valerio Pennicino/Getty Images