West Yorkshire Fire and Rescue have said that 70 firefighters are currently at the scene with assistance also being provided from 4 specialist wildfire units and a helicopter.
The blaze currently has a two-mile "flame front" and an area of 2 square miles is affected by the fire.
The fire had been mainly put out on Monday morning before reigniting in two pockets on Monday evening, with the helicopter being deployed.
Fire crews tackling the wildfire on Monday evening
People are being told to stay away from the moor and local residents are being told to keep doors and windows closed.
Road closures are also in place on Mount Road and Old Mount Road.
The fire started on an area of National Trust land near Black Moss Reservoir and Swellands Reservoir around 7pm on Sunday evening and had a mile-long flame front at its height.
The area is known for its breeding bird habitat and is a popular site for rare curlews. It is also home to short-eared owl and mountain hares.
It follows several weeks of dry weather, which have made the moors extremely vulnerable to fire.
The fire service has said that West Yorkshire Police are conducting an investigation into the start of the fire.
The site of the fire is in a different area to the large fire which burnt across moorland in 2019.
Countryside Manager for the National Trust, Craig Best, said the fire was ''started by people'' and could have easily been avoided.
He said: "It’s so frustrating to see yet another fire on our moors after all the hard work our team have put in to try and restore the landscape after last time.
"Although not on the same area of land as the 2019 fire, this fire has also destroyed a crucial area for rare birds and mammals.
''Unfortunately, this was another fire started by people, and could have so easily been avoided."
The National Trust have reminded people that BBQs and fires are banned on the moor and that people could face a £2000 fine.