Fiji media reported that the death of Ashraf Ali Razat from Omkar in Narere, was confirmed by family members.
Mr Ali, who was 58, was in New Zealand on holiday, staying with relatives in Christchurch, according to the Fiji Times.
Two other men from Fiji killed in the attacks are Imam Hafiz Musa Patel of Lautoka and Ashraf Ali who had moved to New Zealand from Fiji several years ago.
Mr Patel was the chief priest at Lautoka Jame Masjid for about 25 years before migrating to Australia last month.
The Fiji Muslim League expressed its grief over the death of the late Imam.
"Hafiz Musa is one of the tragic victims of the senseless shooting perpetrated by a gunman at two mosque locations in Christchurch, during Friday prayers," the League president Hafizud Dean Khan said.
Ashraf Ali, who was 62, had been living in Christchurch for the past 20 years, the Fiji Times reported.
His family described him as a loving and caring man who never missed any prayer at the mosque, according to the Fiji Times.
Fifty people were killed and another 50 people were wounded in the attacks that have been described as the worst terror attack in New Zealand.