The fire broke out in the ground-floor warehouse of the multi-storey Tazreen Fashion factory, 30 km north of Dhaka, last evening, trapping hundreds of workers on the upper floors.
"The toll exceeded 100, I fear toll could rise as bodies are still being retrieved," an army official told reporters.
Witnesses said the fire at the six-story factory in started on the ground floor and quickly spread to others parts causing the worst fire tragedy in recent years.
Fire service officials earlier said several workers of the factory were trapped inside and took shelter on the rooftop of the structure awaiting rescuers while efforts were underway to extinguish the blaze.
Television footages showed army troops and fire service rescuers bringing out bodies one after another from the debris as hundreds of people including relatives of the victims waiting outside.
Witnesses said the fire spread quickly, prompting army troops from nearby Savar Cantonment to join the rescue campaign.