SEOUL, 26 Oct, 2014 (AFP) - Ham, who finished seventh in the tournament last year, completed his third-round with a birdie on the 18th for a one-over 72.
Former Open winner Y.E. Yang was tied in second place with Kim Seung-Hyuk and Chang Yi-Keun at the Woo Jeong Hills Country Club in Cheonan.
Early morning fog, which has disrupted the entire tournament, delayed the restart of the third round on Sunday morning, forcing a Monday finish on some players.
Ham played the most assured golf amongst the leaders when the third round eventually re-started with two birdies and a lone bogey in his remaining 10 holes for a 72 and a total of three-under 210.
Yang, a two-time Korea Open winner who is looking for a confidence-boosting victory after a poor season, was ahead by a shot when play was stopped on Saturday evening but failed to carry his form into Sunday.
He had a double-bogey at the 13th before picking up a shot at the 15th. The 2009 PGA Championship winner fell two behind Ham when he bogeyed the final hole.
Leading third round scores:
210 - Ham Jeong-Woo (KOR) 70-68-72
212 - Chang Yi-Keung (KOR) 74-70-68, Y.E. Yang (KOR) 72-70-70, Kim Seung-Hyuk (KOR)73-68-71
213 - Choi Ho-Sung (KOR) 67-79-67, Park Ju-Hyuk (KOR) 71-70-72
214 - Kim Gi-Whan (KOR)72-72-70
215 - Noh Seung-Yul (KOR) 73-71-71, Park Jun-Won (KOR) 71-71-73, Hong Soon-Sang (KOR) 72-70-73, Jeon Yun-Cheol (KOR) 67-71-77, Kang Ji-Man (KOR) 69-69-77