The 16-year-old Kim holds a two-shot advantage with his two-day total of 10-under-par 130 at the THB 2,000,000 (approximately US$63,860) Asian Development Tour (ADT) event co-sanctioned by the All Thailand Golf Tour (ATGT).
Thai duo Chinnarat Phadungsil and Sadom Kaewkanjana carded rounds of 64 and 66 respectively to sit in second place with Indonesia’s Danny Masrin (69) at the award-winning Laguna Golf Phuket.
Overnight leader Nattawat Suvajanakorn (71) of Thailand was among five players in tied-fifth while defending champion and countryman Vananyu Rattanaphiboonkij battled to a 74 to sit in tied-89th.
Starting the round three shots off the pace, Kim made a fast charge with three consecutive birdies thanks to his solid iron-play. He went on to grab birdies on holes 13 and 14 before capping off a bogey-free round and move atop the leaderboard.
“It was a really good round today, I started off well with three straight birdies but then it started to get windier in the afternoon and I was scrambling in the middle of my round.
“I am striking my irons well and all my birdies were inside 10-feet. I still feel good about how I played but obviously there is a lot of golf left to play so my position right now doesn’t matter that much,” said the Korean, who only missed three greens.
Chinnarat, a three-time Asian Tour winner, took advantage of his hot putter to trade seven birdies against one bogey and put himself in contention.
“I started out with an easy birdie on the first hole after I hit my nine-iron to three-feet. I was hitting it well all day but I think the biggest difference about my round was that I was putting better,” said the Thai, who only totalled 25 putts.
“I did well in the first nine holes but slowed down towards the back. But I am still very happy with my position and I will stay positive,” added the 30-year-old.
The halfway cut was set at one-under-par 139 with 57 players advancing to the weekend rounds.
The Singha Laguna Phuket Open is the Tour’s third stop in Thailand this season and is celebrating its third straight edition on the ADT this year.
Leading second round scores:
130 - Joohyung Kim 65 65
132 - Chinnarat Phadungsil 68 64, Sadom Kaewkanjana 66 66, Danny Masrin 63 69
133 - Nattawat Suvajanakorn 62 71, Janne Kaske 67 66, Miguel Carballo 65 68, Jack Murdoch 66 67, Tawan Phongphun 66 67
134 - Poom Pattaropong 67 67, Tarik Can 66 68, Piya Swangarunporn 65 69, Nitithorn Thippong 63 71, Suradit Yongcharoenchai 68 66