The Thai rising star, who was the co-overnight leader, struggled with his putting but scrambled to a 13-under-par 131 total at the US$300,000 event which is the curtain raiser for the 10th Asian Tour season celebrations.
Thai duo Thanyakon Khrongpha and three-time Asian Tour winner Chawalit Plaphol, who shot a 67 and 66 respectively, were a further two shots back on 133 at the Royal Mingalardon Golf and Country Club.
Marcus Both of Australia blitzed the front nine with seven-under-par 29 to tie for the second lowest first nine score on the Asian Tour. He eventually settled for a 66 to share fourth place with Joonas Granberg (69) of Finland and Hung Chien-yao (67) of Chinese Taipei on 134.
There was heartbreak for title holder Kieran Pratt of Australia, who was disqualified for arriving late for his tee time while overnight leader Chapchai Nirat of Thailand shot a 72.
Kiradech, who lost-in a playoff to Pratt last year, is on the right path to erase that defeat but he is wary of the talented challengers, who are hot on his heels.
"I've had a lot of experience in the last few years of being in contention and winning. Right now, I'm not thinking about winning yet because it isn't the last day. I have two more rounds and I want to do my best and give myself a chance," said the 23-year-old.
Having shot a 64 in the opening round, the burly Thai hopes to rediscover his putting touch in the weekend. "Whatever happens, I want to do my best. I feel my putting stroke isn't as smooth as it was yesterday (Thursday) but I won't do much change, just tweak a bit of my back swing."
Thanyakon has not tasted victory since his 2010 win on the Asian Development Tour (ADT) and was clearly delighted to be within touching distance of his compatriot.
"I'm very happy to see my name on the leaderboard. The last time I won was on the Asian Development Tour in 2010! It has been a long time. I hope I can keep up with Kiradech," said the 22-year-old.
Australia's Both needed only nine putts on his superb front nine but wobbled on his return when he bogeyed 16 and 17 before adding his eighth birdie of the day on the last.
"It might sound very stupid but I didn't play that well. I sort of hit everything nicely on the greens and holed everything. I had nine one putts on the front nine. That was pretty much the reason why. I hit it okay but not amazingly well. It sort of caught up with me on the back nine," said the two-time Asian Tour winner.
Korea's Baek Seuk-hyun, 22, took advantage of the ideal scoring conditions and birdied three out of the four par fives for a 68 and 135 total to trail Kiradech by four shots going into the penultimate round.
"I found all the fairways on the par fives and took advantage of that. I made easy birdies especially on the 14th hole when I missed a five feet eagle chance. You need good tee shots and putting here because the greens are very tricky," said Baek.
The halfway cut was set at three-under-par 141 with a total of 68 players making the weekend rounds.
Scores after round 2 of the ZAYKABAR MYANMAR OPEN being played at the par 72, 7218 Yards RMGcC course (a- denotes amateur):
131 - Kiradech APHIBARNRAT (THA) 64-67.
133 - Thanyakon KHRONGPHA (THA) 66-67, Chawalit PLAPHOL (THA) 67-66.
134 - Joonas GRANBERG (FIN) 65-69, Marcus BOTH (AUS) 68-66, HUNG Chien-yao (TPE) 67-67.
135 - BAEK Seuk-hyun (KOR) 67-68, Darren BECK (AUS) 66-69, Arnond VONGVANIJ (THA) 68-67.
136 - Lionel WEBER (FRA) 67-69, Mardan MAMAT (SIN) 67-69, HWANG In-choon (KOR) 66-70, Chapchai NIRAT (THA) 64-72.
137 - David LUTTERUS (AUS) 70-67, HU Mu (CHN) 67-70, Angelo QUE (PHI) 69-68, CHOO Tze Huang (SIN) 67-70, Prom MEESAWAT (THA) 65-72, Rahil GANGJEE (IND) 71-66.
138 - Rikard KARLBERG (SWE) 67-71, Berry HENSON (USA) 70-68, Ajeetesh SANDHU (IND) 70-68, Thaworn WIRATCHANT (THA) 71-67, Koichi KITAMURA (JPN) 69-69, Namchok TANTIPOKHAKUL (THA) 70-68, Danny CHIA (MAS) 68-70, Nicholas FUNG (MAS) 70-68, KIM Seng-yong (KOR) 72-66.