Firefighters from across the county tackled the blaze covering around 50 acres in the White Wells area on Saturday afternoon.
Officers used beaters, leaf blowers, backpacks and portable water pumps to try and extinguish the flames.
Initially four engines were sent to the scene shortly after midday. This later increased to 14 crews as the fire service attempted to stop the fire spreading.
Footage posted on Twitter showed a line of flame stretching across the moor and a large cloud of smoke rising into the air.
“The intense heat, steep slopes and rough terrain are causing the fire to spread rapidly whilst we try to get near the flames.” said Martyn Hughes, a watch manager at North Yorkshire Fire and Rescue Service.
— Martyn Hughes NYFRS👨🚒 (@Har_DistrictWM)April 20, 2019
The fire was still burning after 8pm. “Despite frantic efforts by all involved it looks like the moor will continue to burn long in to the sunset,” said Mr Hughes.
West Yorkshire Fire and Rescue Service had warned the public on Friday about the risk of four on moorland.
It urged visitors to protect the landscape and wildlife by discarding cigarettes responsibly, reporting suspicious activity and refraining from lighting a fire in the countryside.