Aphibarnrat, who started his third round in third position, made five birdies in a bogey-free performance to move to -18 for the tournament, opening up a slender one stroke advantage going into the last day.
Frenchman Romain Wattel carded the best score of the day, a seven-under-par 64 in a round that included seven birdies, and he climbed seven places up the leaderboard into second.
Joel Stalter, also from France, is in sole possession of third on -12 after he struggled to replicate his form from the opening two rounds whilst England's Lee Westwood heads a group of three players in a share of fourth on -11.
The former world number one made five birdies and one bogey for a four-under 67 and is joined by Germany's Sebastian Heisele and Sweden's Joakim Lagergren, who posted rounds of 68 and 70 respectively.
South African's Justin Walters and George Coetzee, Canadian Austin Connelly and Italian Matteo Manassero are all sitting on -9, five strokes off the lead, after signing for rounds of 65, 68, 66 and 68 respectively.