The world number three carded a six-under par round of 65 in Miyazaki on the eastern coast of the southern island of Kyushu to share the lead with home player Hideto Tanihara and Australian Brendan Jones.
The Englishman came home in 30, picking up birdies at each of the last three holes, in the Japanese tour event.
European Ryder Cup star Nicolas Colsaerts is tied for eighth place, four off the lead.
The event has been won by Seve Ballesteros, Tom Watson, Tiger Woods and Padraig Harrington in the past.
-6 Hideto TANIHARA, Luke DONALD, Brendan JONES
-4 Koichiro KAWANO, Shunsuke SONODA
-3 S K HO. Hirohito KOIZUMI
-2 S J PARK, Shingo KATAYAMA, Hyun-Woo RYU, Hiroyuki FUJITA, Tomohiro KONDO, Nicolas COLSERTS, Shigeru NONAKA, Nobuhiro MASUDA