The 2023 Nonthaburi Challenger was a professional tennis tournament played on hard courts. It was the 4th edition of the tournament which was part of the 2023 ATP Challenger Tour. It took place in Nonthaburi, Thailand from 2 to 7 January 2023.
Singles main-draw entrants
Seeds
1 Rankings are as of 26 December 2022.
Other entrants
The following players received wildcards into the singles main draw: Maximus Jones Palaphoom Kovapitukted Thantub Suksumrarn
The following players received entry from the qualifying draw: Alafia Ayeni Evgeny Donskoy Giovanni Fonio Dayne Kelly Lucas Pouille Henri Squire
Champions
Singles
Dennis Novak def. Wu Tung-lin 6–4, 6–4.
Doubles
Marek Gengel / Adam Pavlásek def. Robert Galloway / Hans Hach Verdugo 7–6(7–4), 6–4.