Neymar was included in a list of 55 pre-selected players for the Brazil national team. His absence from the squad had lasted more than 900 days following a knee injury sustained in October 2023.

In October 2023, Neymar suffered a tear of the anterior cruciate ligament and meniscus in his left knee. He remained inactive for nearly one year. In early 2026, he underwent knee cleaning surgery and was out of play for two months.

Prior to the knee injury, Neymar underwent surgery on his right ankle in March 2023 and was inactive for more than four months. On September 8, 2023, during a 5-1 victory over Bolivia in a World Cup qualifier, Neymar scored his 79th goal for the national team, surpassing Pelé's record of 77 goals. He had previously tied the record with a goal against Croatia in the quarterfinal match of the 2022 World Cup. Brazil was eliminated by Croatia in that match via a penalty shootout. Neymar had returned to play in the round of 16 at the 2022 World Cup after being substituted out of Brazil's debut match against Serbia due to an injury.

Neymar has participated in 13 World Cup matches over a 12-year period, scoring eight goals and providing four assists. He was not selected for the Brazil squad for the 2010 World Cup when Dunga was the coach. Prior to the 2018 World Cup, he suffered a fracture in his fifth metatarsal, undergoing surgery that kept him out of play for three months. He played in five matches at the 2018 tournament, scoring two goals and providing two assists, before Brazil was eliminated by Belgium in the quarterfinals. During the 2014 World Cup, he sustained a knee injury from a collision with Camilo Zúñiga. A medical report stated this injury was close to paralyzing him. Brazil subsequently lost to Germany 7-1 in the semifinals of that tournament at the Mineirao stadium in Belo Horizonte.

In international tournament play outside the World Cup, Neymar won the 2013 Confederations Cup with Brazil, where they defeated Spain in the final at the Maracanã stadium. In 2016, Brazil won the Olympic gold medal in football at the Maracanã stadium. Four years prior, Brazil won the silver medal in football at the London Olympics. Neymar suffered a right ankle injury shortly before the start of the Copa América tournament in 2019; Brazil won the title that year. In 2021, Brazil lost the final of the Copa América to Argentina, with Neymar being named the best player of the tournament.