Ko, 16, carded a 3-under 69 at Linkou Miramar Golf & Country Club, finishing at 11-under-par 205 for her first win since turning pro in October.
The much-heralded rookie made her professional debut last month at the CME Group Titleholders on the LPGA Tour, tying for 21st place.
With the showing, she was granted full membership on the LPGA Tour starting next year.
The Taiwan event is co-sanctioned on both the Taiwan LPGA and Korean LPGA tours.
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