The Awami League leader breathed his last around 12:45 am at Bangabandhu Sheikh Mujib Medical University (BSMMU), said his son Mahmud Hossain, a Professor of Khulna University.
He left behind his son and a host of relatives to mourn his death.
Mozammel, also the district unit Awami League President, was elected MP from Bagerhat-1 and 4 constituencies in 1991, 1996, 2008, 2014 and 2018.
He had been serving as the president of district unit Awami League since 1984.
Born in August 1, 1940, the senior Awami League leader was the former state minister of Women and Children Affairs Ministry.
A namaz-e-janaza of the Awami League leader was held at the South Plaza of the Jatiya Sangsad Bhaban in the morning. Later, he will be taken to Bagerhat.
Sheikh KamruzzamanTuku, general secretary of district unit Awami League, said the body of the Awami League leader will be kept in front of the district unit Awami League office at Rail Road from 12 pm to 1 pm so that people can pay tributes.
Around 2 pm, another namaz-e-janaza of Mozammel will be held at Sheikh HelalUddin Stadium.
He will be buried at the family graveyard following a namaz-e-janaza at Kochubunia High School ground in Morelganjupazila in Bagerhat.
Meanwhile, President Abdul Hamid, Prime Minister Sheikh Hasina and Speaker of the Jatiya Sangsad Dr Shirin Sharmin Chaudhury expressed deep shock at the death of the Awami League leader.