The fire at Dalton Mills in Keighley started on Saturday evening and was tackled through the night by about 100 firefighters.
The building is Grade II listed.
The blaze destroyed one four-storey wing of the 19th century building in Dalton Lane. The cause is being investigated.
Fire crews were alerted to the blaze shortly before 7pm on Saturday night.
It was not extinguished until about midnight. Crews remained at the scene yesterday damping down the remains of the wrecked building.
When crews arrived there were flames coming out of the roof and windows.
Fire crews stopped it spreading to the rest of the building.
Dalton Mills once employed more than 1,000 workers.
The partially restored mill has been used as the setting for television dramas and Bollywood films.
It had a starring role as Marlborough Mills in the BBC adaptation of North and South.
Last month it was reported that Dalton Mills failed to sell at auction.