Shahina Siddiqui of the Islamic Social Services Association in Winnipeg says the memorial will be held at the city's Grand Mosque on Monday evening.
Hamid Farooq lost his entire family to the fire last Tuesday — his wife, mother and three daughters died.
He was at work when the fire broke out.
His youngest daughter was only four months old and had been on life support, but died Friday afternoon.
Siddiqui says both the Muslim community and the general community have expressed a desire to pay their respects to the family members who died, as well as to Farooq.
Police said Friday that investigators believe the fire was accidental.
Siddiqui was with Farooq at the hospital on Friday. She said he is holding up well and that his faith is strong.
"To have your entire family wiped out, it's difficult. We are praying God will see him through this," she said.
The Islamic Social Services Association, which has been helping to support Farooq and his extended family, is also raising funds for the family. The cost to return the family to Pakistan for interment could exceed $60,000.
The Assiniboine Credit Union has opened a trust fund to accept donations to help the family.
Siddiqui said it's touching how much support has been shown for the family.
"As sad as this story is, and as tragic the event, it has also shown the best of human spirit," she said.