Junior Lieutenant Panupong Wongpakpaiboon succumbed after spending 28 days being treated in hospital for third-degree burns in 60 per cent of his body. He had initially been taken to the Queen Sirikit Naval Hospital in Sattahip district before being transferred to Rayong Hospital.
Panupong was stationed at Flotilla 2, Frigate Squadron 1 of the Royal Thai Fleet after graduating from the Armed Forces Academies Preparatory School in 2013.
His family has said nothing about funeral arrangements.
Several victims are still in severe condition, with many on ventilators.
The nightclub caught fire at about 1am on August 5, killing 13 people on the spot and injuring scores of others.
The pub was operating without proper permits and had undergone illegal modifications.
The owner of the pub, Somyos Panprasong, 55, has been charged with recklessness causing death and injuries and operating an entertainment venue without permission.