Initial investigations showed the fire that engulfed the eight-storey building was started by a woman who set herself ablaze, following a quarrel with her husband.
President Chen Shui-bian promised an immediate investigation into the blaze.
"The fire and police authorities must find out the cause of the blaze to ensure that identical events would not recur," he said.
Doctors said most of the victims had suffocated to death, but some had died after jumping off the top floors to escape the flames.
Residents of the high-rise initially suspected arson to be the cause behind the fire.
But senior prosecutor, Lin Po-Chih, said an initial investigation showed it was caused by a woman who had doused herself with solvent.
The woman suffered 90% burns and is in a critical condition.