Peau, who won gold for New Zealand in the superheavyweight division in Edinburgh in 1986, recently underwent brain surgery.
Born in Samoa as Ti'a James Senio Peau, he grew up in Auckland.
After his Commonwealth Games success as an amateur, which also included the Australian heavyweight title, Peau turned professional in 1988 and fought under the name Jimmy Thunder.
Peau won two world heavyweight belts during his career - the WBF in 1993 and IBO in 1994.
He was famous for knocking out American Crawford Grimsley with his first punch in 1997.