Jaidee, who is in the hunt for his first European Tour win since 2009, takes a one-stroke lead over Joost Luiten and Ross Fisher into Sunday's final round at Celtic Manor in Newport.
It was a roller-coaster round for Jaidee, who finished with a four-under 67 for the round and seven-under 206 for the tournament. Jaidee carded seven birdies and three bogeys in the round. He birdied the 18th to take sole possession of first place.
Luiten closed strongly on the back nine with three birdies and an eagle en route to a 64.
Fisher, who led after two rounds, also birdied 18 to finish at even-par 71 for the day.