Miguel and Gilberto Rodriguez Orejuela, 62 and 67 years old respectively, pleaded guilty to on charge of conspiring to import 200,000 kilograms of cocaine into the United States.
Both also pleaded guilty to one charge of conspiring to commit money laundering.
The sentencing came after the brothers reached a plea agreement under which they forfeited 2.1 billion dollars to be levied against their property and business assets, which include more than 300 companies in Colombia, the Bahamas and Panama.
"I ask my family for forgiveness because I have made them suffer for this," said Miguel as Judge Federico Moreno was about to hand down the sentence.
He also asked "the American people and its authorities" for forgiveness. But his brother Gilberto had no apologies. "I submit myself to American justice," he said before choking on his words.
Final blow
In a statement, US Attorney General Alberto Gonzales said the brothers' guilty plea "signals the final, fatal blow to the powerful Cali Cartel."
Gilberto Rodriguez Orejuela, known as "the Chess Player," was extradited to the United States in December 2004. Three months later Colombian authorities extradited his brother Miguel, also to Miami.
Both initially pleaded innocent.
‘High level traffickers’
The brothers, who founded the now defunct drug cartel in the Colombian city of Cali, were once considered among the world's most powerful criminals.
During its heyday in the 1980s and early 1990s the cartel controlled 80 percent of the cocaine smuggled into the United States, according to US officials.
At times they would use a Boeing 747 to ferry bales of cocaine to Mexico for transshipment into the United States, according to the US charges.
They would hide the US-bound drugs inside concrete posts, frozen vegetables, pumpkins, lumber, sacks of coffee, chlorine cylinders and even ceramic tiles.
"These brothers rank as arguably the highest-level trafficking figures to ever occupy US jail cells," said Julie Myers, a top official with the Immigration and Customs Enforcement agency (ICE).
The siblings were accused of running drug trafficking and money laundering operations from the Colombian prison in which they were held after being sentenced to 15 years in 1995.
The federal investigation in the case lasted 14 years and included charges against nearly 100 suspects