Sandoval County Fire Chief James Maxon says the fire started in the oil well about noon Tuesday and was extinguished about 2 1/2 hours later.
He says the cause of the fire isn't immediately known.
Maxon says three units of county firefighters were called in to help battle the blaze because the nearest fire station is 43 miles away.
He says the three injured employees were taken to a hospital by personal vehicles and their names and conditions aren't immediately available.
The oil rig is located in a desolate area off Route 550 near Lybrook.
Maxon says there was a fire at the same location a year ago but nobody was injured that time.