Frank, 63, collapsed in the yard of the Giudice's home in Towaco, N.J. He had previously appeared on episodes of Real Housewives with his son, daughter-in-law and granddaughters.
"Sadly it is true that the father of my client and friend Joe Giudice passed away today @Teresa_Giudice asks for privacy and prayers," said family rep Wendy Feldman in a statement on Twitter.
"Joe and his dad were chasing the dog Simba and suddenly Franco fell ill," Feldman told Us Weekly.
Joe and Teresa were due to be sentenced in federal court on July 8, after pleading guilty to several fraud charges. The Giudices, who originally faced 41 counts of federal fraud, including bankruptcy and wire fraud, reached a plea deal last March.
Teresa could face less than two years in prison, while Joe faces at least three.
But they will have to wait a little longer to hear their punishments. The U.S. Attorney's Office told the Star-Ledger on Thursday that it had pushed back the Giudices sentencing date to September 23. They emphasized that it was not because of Frank's death.