Solari, who had struggled with Parkinson's disease for at least a decade, was found dead near an indoor pool at his house in the provincial town of Ituzaingo, about 30km west of the Argentine capital, Buenos Aires, authorities said, without identifying a cause of death.
His family confirmed his death on social media, saying they would hold a public funeral to allow people to bid farewell to the rock legend.
As news of his death broke, fans began gathering at his home, some bearing flowers and wearing T-shirts printed with his nickname.
"We will mourn as is fitting, listen to his songs and, above all, take care of one another, as he taught us to do," the family's statement said.
As the lead singer of Patricio Rey y sus Redonditos de Ricota - known more simply as Los Redondos - Solari became a countercultural icon for disaffected Argentines coming of age in the 1980s as their country transitioned from a bloody military dictatorship to a democracy characterised by new-found freedoms but also instability and hyperinflation.
During the consumerist frenzy that gripped Argentina in the 1990s under the free-market policies of then-president Carlos Saul Menem, Solari's classic rock anthems, punchy dance tunes and cryptic lyrics gave voice to a spirit of rebellion against the excesses of capitalism and influences of foreign powers. Los Redondos released 10 studio albums, eschewing major record labels to maintain artistic independence.
The band broke up in 2001, but Solari found continued success as a solo artist, releasing five more albums under his own name that mixed mainstream rock and electronic influences and drawing hundreds of thousands of fans to parks and stadiums across Argentina.
At a massive concert in 2016, he announced he had been diagnosed with Parkinson's disease.
"Mr Parkinson is nipping at my heels. But here I am," he said.
The crowd went wild. He later retired from touring, speaking candidly in interviews about the debilitating effects of the disease.
Tributes poured in from politicians, artists and soccer stars across the country.
The Argentine Soccer Association said Solari's voice "became a popular rallying cry" and "echoed in the stands" of the soccer-crazed country.
The Grandmothers of Plaza de Mayo, a prominent activist group that sought to find relatives who had been killed or "disappeared" by the 1976-83 dictatorship, said the singer "inspired society as a whole to doubt, to question and to think critically".
Cristina Fernández de Kirchner, Argentina's former president who is serving a corruption sentence under house arrest, posted one of his famous lyrics on social media, popularised as a call to live courageously: "Just living costs you your life."
Solari is survived by his wife, Virginia Mones Ruiz, and 25-year-old son Bruno.
