Muhammadu Bello Masaba "passed away on Saturday in his home surrounded by his family", Salahu Bello told AFP by telephone from Niger state, central Nigeria.
In 2008, a Sharia court in the state capital, Minna, held him in "incendiary contempt of religious laws and contracting unlawful marriage to 86 wives".
He was told to keep only four -- the maximum allowed by Islam. But Masaba -- known affectionately as "Baba" (father) -- refused, insisting he had not breached any religious tenets.
Salahu Bello said, "He died at the age of 93 and anyone who lives to that age should be expected to have health challenges."
"Baba wouldn't take medicine and wouldn't advise people to take medicine. That is how he lived. His family is intact. All his 86 wives were around him when he died.