UPDATED: The fire was extinguished at just after 3pm.
Huge flames can be seen on grassland near Dicky Sykes Lane, between Ackworth and Fitzwilliam.
Eleven fire engines are at the scene and crews are tackling the blaze from Second Avenue and Dicky Sykes Lane.
The flames had been approaching a farm but the buildings are believed to be safe.
West Yorkshire Police were called to assist the fire service at 1.40pm.
West Yorkshire Fire Service said:
"This was a fire in the open involving standing corn 300 metres by 300 metres.
"There was concern that the fire was moving towards a nearby farm so crews attended the other side of the field to prevent any risk to this building.
"A combine harvester was also used to create a fire break. Pockets of fire remain in the area."
Last week, over Â£15,000 of damage was caused by a crop fire near Sandal that is thought to have been started deliberately.
Video: Leigh Westerman