Pavarotti had been diagnosed with pancreatic cancer last year and underwent further treatment last month.
His manager Terri Robson said in an email statement to The Associated Press that Pavarotti died at his home in Modena, Italy, at 5am local time today.
"The Maestro fought a long, tough battle against the pancreatic cancer which eventually took his life. In fitting with the approach that characterised his life and work, he remained positive until finally succumbing to the last stages of his illness," the statement said.
His family and close friends were at the home with the opera star.
For serious fans, the unforced beauty and thrilling urgency of Pavarotti's voice made him the ideal interpreter of the Italian lyric repertory, especially in the 1960s and '70s when he first achieved stardom.
For millions more, his charismatic performances of standards such as Nessun dorma, from Puccini's Turandot, came to represent what opera is all about.
Instantly recognisable by his charcoal black beard and tuxedo-busting girth, Pavarotti radiated an intangible magic that helped him win hearts in a way Placido Domingo and Jose Carreras - his partners in the Three Tenors concerts - never quite could.
"I always admired the God-given glory of his voice - that unmistakable special timbre from the bottom up to the very top of the tenor range,'' Domingo said in a statement from Los Angeles.
"I also loved his wonderful sense of humour and on several occasions of our concerts with Jose Carreras - the so-called Three Tenors concerts - we had trouble remembering that we were giving a concert before a paying audience, because we had so much fun between ourselves,'' he said.
The tenor, who seemed equally at ease singing with soprano Joan Sutherland as with the Spice Girls, scoffed at accusations that he was sacrificing his art in favour of commercialism.
"The word commercial is exactly what we want,'' he said, after appearing in the Three Tenors concerts.
"We've reached 1.5 billion people with opera. If you want to use the word commercial, or something more derogatory, we don't care. Use whatever you want.''
In the annals of that rare and coddled breed, the operatic tenor, it may well be said the 20th century began with Enrico Caruso and ended with Pavarotti.
Other tenors - Domingo included - might have drawn more praise from critics for their artistic range and insights, but none could equal the combination of natural talent and personal charm that so endeared him to audiences.
"Pavarotti is the biggest superstar of all,'' the late New York Times music critic Harold Schonberg once said.
"He's correspondingly more spoiled than anybody else. They think they can get away with anything. Thanks to the glory of his voice, he probably can.''