The 2023 Nonthaburi Challenger III was a professional tennis tournament played on hard courts.

It was the 6th edition of the tournament which was part of the 2023 ATP Challenger Tour.

It took place in Nonthaburi, Thailand from 16 to 22 January 2023.

The following players received wildcards into the singles main draw: The following players received entry into the singles main draw as alternates: The following players received entry from the qualifying draw: The following player received entry as a lucky loser: