The world number 181 took advantage of a break in the otherwise inclement weather at the WTA 125k series hard-court event, beating Noppawan Lertcheewakarn in straight sets.
However, top seed Peng Shuai was not so lucky and will have to come back on Thursday to face Ilona Kremen after persistent rainfall prevented her from taking to the court.
Wang completed her 6-1 7-6 (7-2) victory over Lertcheewakarn in 92 minutes, having dominated the second-round match.
The local favourite converted four break points in the opening set, enjoying particular success on her Thai opponent's second serve.
Lertcheewakarn raised her game to force a tie-break in the next set, but Wang duly reasserted her control to seal a last-eight spot against either Peng or Kremen.