The Defense Ministry here in the capital is hosting the event, which is being held with full observance of the health protocols.
Members of the martyr’s family as well as political and defense and scientific officials are attending the funeral procession.
A message from Leader of the Islamic Revolution Ayatollah Seyed Ali Khamenei was read out at the ceremony.
An honor guard carried the casket of Martyr Fakhrizadeh to a podium where Qaris recited verses from the Quran.
Fakhrizadeh, a senior nuclear and defense scientist, was assassinated by unknown gunmen in a small city east of Tehran on Friday evening.
After sustaining injuries from a car explosion and bullets, Fakhrizadeh was taken to the hospital with a helicopter, but succumbed to injuries a few hours later.
Iranian officials have vowed a severe punishment for those behind the terrorist attack.