On 10 July 2020, Makoundou signed his first professional contract, a three-year deal with Cholet of the
LNB Pro A. On 20 January 2021, he recorded 20 points and eight rebounds in an 89–71 loss to
Hapoel Holon. After averaging 10.4 points and 5.2 rebounds per game in the
2020–21 Basketball Champions League, he was named
Champions League Best Young Player.
AS Monaco (2022–2026) Makoundou signed a four-year deal with
AS Monaco on July 23, 2022. In September 2023, Makoundou was loaned out to
Budućnost of the Montenegrin
Prva A Liga, the
ABA League and the
EuroCup until the end of the season. On July 1, 2024, he signed with
Türk Telekom of the
Basketbol Süper Ligi (BSL), again on loan from Monaco. On March 5, 2026, AS Monaco announced it had reached an agreement with Makoundou to terminate the player's contract.
Fujian Sturgeons (2026–present) On March 10, 2026, he signed with
Fujian Sturgeons of the
Chinese Basketball Association (CBA). ==National team career==