Boyd had one bogey en route to a 5-under 67 and is tied with Jean-Baptiste Gonnet, who also shot 67 in the second round, at 11-under 133 after 36 holes.
They are one stroke ahead of Branden Grace, who had an eagle and three birdies for a second consecutive 67.
Nicolas Colsaerts, who picked up his first European Tour title last year at the China Open, is in fourth at 9-under. He had an eagle at No. 2 for the second consecutive day and also had five birdies and two bogeys.
First-round leader Mathew Baldwin turned in a 1-over 73 and slipped into a tie for 16th.
Boyd, playing the back nine at the Binhai Lake Golf Club first, was one over after eight holes before finishing the side with a birdie at 18. He added a birdie at the second hole and moved into contention with consecutive birdies over Nos. 4-6. He also birdied the ninth hole.
Gonnet was 1-over after four holes but had three birdies over five holes to make the turn at 2-under. He had a similar string on his second nine for a share of first.