Varatchaya "Pias" Wongteanchai (Thai: วรัชญา วงค์เทียนชัย; born 7 September 1989) is a former professional tennis player from Thailand.

In February 2012, Wongteanchai made her WTA Tour main-draw debut at her home tournament, the Pattaya Open.

She qualified for the main draw by defeating Hsu Wen-hsin in three, and Misa Eguchi in straight sets.

She was then awarded a wildcard into the Pattaya Open, where she defeated Annika Beck 6–3, 6–3 but lost to Marina Erakovic in the second round.

Partnering Jessica Moore, Wongteanchai won the doubles title at the 2016 Bucharest Open, defeating Alexandra Cadanțu and Katarzyna Piter in the final in straight sets.