Juventus wrapped up a ninth successive Scudetto when they beat Sampdoria at home last weekend, before slipping to a surprise 2-0 defeat against Cagliari on Wednesday in a game in which Ronaldo failed to add to his 31 league goals for the season.
Higuain turned in from close range just six minutes in after pouncing on Adrien Rabiot's flick from Federico Bernardeschi's corner.More news: Basketball-WNBA to play season at single site in Florida without fans
But Diego Perotti inspired a Roma fightback setting up Nikola Kalinic to nod in the equaliser after 23 minutes.
Perotti stretched the lead seven minutes into the second half, sweeping home inside the area - via a deflection off Merih Demiral - after collecting Nicolo Zaniolo's perfectly weighted pass.
Inter Milan finish just one point behind the champions after winning the three-team race for second spot.More news: Verstappen eyes Silverstone 'fighting chance' against Mercedes' untouchables
Lazio finished fourth with 78 points and Coppa Italia winners Napoli ended the season seventh with 62 points.
Portuguese ace Ronaldo has won the Golden Shoe four times during his illustrious career, the last of those coming in the 2014-15 season, when he scored a remarkable 48 goals in 35 La Liga games with Real Madrid.
The Italian will now be determined to try and break the Serie A record for goals scored in one season, which is held by Gonzalo Higuain after he found the back of the net 36 times in the 2015/2016 season.More news: No secret Phillipe Coutinho wants to come back to Premier League
The season concludes on Sunday with Lecce and Genoa playing Parma and Hellas Verona respectivel hoping to avoid joining Brescia and SPAL down in Serie B.