The Belo Horizonte-based club moved 16 points clear of second-placed Atletico Paranaense, who lost 2-1 to Criciuma to hand the 2013 Brazilian championship to Cruzeiro.
Goals in the final 20 minutes to Julio Baptista and Ricardo Goulart wrapped up Cruzeiro's victory at Vitoria's Estadio Manoel Barradas as Marcelo Oliveira's team notched their fourth consecutive win in Brazil's top flight.
Willian started Cruzeiro's win on Wednesday with a goal eight minutes before half-time, running onto Dagoberto's through-ball to finish past Vitoria goalkeeper Wilson.
Cruzeiro were confirmed as champions during the break as Atletico PR's match finished in Criciuma but the new title-holders suffered a blow just after half-time when Dinei converted for Vitoria in the 51st minute.
But the visitors responded in the 71st minute, pulling Vitoria's defence apart as Dagoberto teed up Baptista, while Goulart's smart finish from inside the box 10 minutes later completed Cruzeiro's 23rd win of the campaign.
In Criciuma, the home side led 2-0 at half-time thanks to Fabio Ferreira's sixth-minute strike and Wellington Paulista's penalty just before the half-hour mark and although Atletico PR fought back after the break through Paulo Baier's goal, the visitors were unable to win and stay in the hunt for the title.
Last season's champions Fluminense improved their chances of survival with a 2-0 win against cellar-dwellers Nautico.
Dorival Junior's Fluminense side moved to 16th with 39 points and 10 wins, one spot out of the relegation zone and ahead of Bahia (39 points, nine wins).
