A jury in federal court in Camden, N.J., found Scarfo, 49, and three co-defendants guilty of racketeering conspiracy and a long list of other charges Thursday. Salvatore Pelullo, 47, a Scarfo associate, and two brothers, William and John Maxwell, who worked for First Plus Financial, were also convicted.
Three lawyers allegedly involved in the plot were acquitted.
Scarfo and Pelullo face sentences of at least 30 years and the Maxwell brothers up to 20 years. Sentencing was scheduled for October.
"Little Nicky" Scarfo, 85, headed the Philadelphia mob for a few years in the 1980s and was known as a ruthless and violent leader. He has been in prison since 1988 and is expected to die behind bars.
One of his three sons changed his name and cut ties to his family while another died in 2013, years after a suicide attempt left him in a vegetative state.
After the verdict, Pelullo's family suggested that federal prosecutors had used the Scarfo name to build up a case.
"The biggest crime he ever committed was becoming friends with Scarfo," his sister, Mary Louise Jalilvand of Elkins Park, Pa., told the Philadelphia Inquirer. "It was guilt by association."