Tennis at the 2023 Pan American Games – Men's singles

The men's singles tennis event of the 2023 Pan American Games was held from October 23 to 29 at the Tennis and Racket Sports Training Centre in Santiago, Chile.

Facundo Díaz Acosta from Argentina defeated home athlete Tomás Barrios in the final, 6–4, 7–5, to win his first Pan American gold medal.

Thiago Monteiro from Brazil won the bronze medal, defeating his fellow countryman Gustavo Heide in the bronze-medal match, 1–6, 6–3, 7–6.

Qualification
Each National Olympic Committee (NOC) can enter up to three players. Qualification for the event is primarily through the ATP or ITF ranking, and all athletes must fulfill the qualification requirements for the 2024 Olympic Games. There are 41 quota places available for men's singles.

There are four places available through regional qualification: two in the 2022 South American Games, and two in the 2023 Central American and Caribbean Games. There is also one place available through the 2021 Junior Pan American Games. All of these places are for the athletes, not for their NOC.

Three places are guaranteed to the host nation, Chile.

The definitive entry list was published on 21 October 2023 and 37 athletes entered the event. The seeding was defined by the ATP rankings of the players. The first round was played by 10 athletes, who were drawn randomly among unseeded players. The remaining athletes started in the round of 32.

Seeds
• # (champion, gold medalist)

• # (final, silver medalist)

• # (third round)

• # (semifinals, bronze medalist)

• # (quarterfinals)

• # (semifinals)

• # (third round)

• # (quarterfinals)

• # (third round)

• # (second round)

• # (quarterfinals)

• # (second round)

• # (second round)

• # (third round)

• # (third round)

• # (quarterfinals)

Draw
The results were as follows: