The 33-year-old returned to his childhood club Santos in January and played a key role in their survival in the Brazilian top flight, playing through the pain and scoring five times in their last four matches
In a statement on Monday, Santos said the surgery was performed by the Brazilian national team's doctor Rodrigo Lasmar.
"An arthroscopy was performed to treat a medial meniscus injury. The surgery was a success, and the athlete is doing well," they added.
Santos did not provide a timeline for his return, though Brazilian outlet Globo Esporte reported his recovery would take up to a month.
Neymar, Brazil's leading goalscorer with 79 goals, has not featured for the five-time World Cup winners since 2023 due to a succession of injuries.
In October, national team head coach Carlo Ancelotti said he must be fit if he is to earn a recall to the squad for the June 11th to July 19th World Cup in Canada, Mexico and the United States.
Brazil will face Scotland, 2022 World Cup semi-finalists Morocco and Haiti in Group C.