The cause of the blaze, which broke out in the early hours of Thursday around the hospital's intensive care, maternity and neonatal care wards, remains unknown, Saudi Civil Defense spokesman Maj. Yahya bin Abdullah al-Qahtani said.
There was no immediate breakdown of the victims or further details available.
The kingdom has suffered a number of large-scale accidents this year, including a crane collapse that killed 111 and a crush that killed at least 2,411 during the Hajj pilgrimage in September, according to an Associated Press count.
The AP figure, which is three times higher than the official toll, establishes the Sept. 24 crush at Mina as the deadliest incident in the history of the annual pilgrimage. It is based on state media reports and officials' comments from 36 of the over 180 countries that sent citizens to the hajj. Hundreds remain missing.
The kingdom has also been struggling with multiple pressures. It has launched an aggression on neighboring Yemen, and is dealing with low oil prices that are straining its budget.