Ewerthon Henrique de Souza (born 10 June 1981) is a Brazilian former professional footballer who played as a forward or winger. He was known for his pace, trickery and long shots, and played for clubs in Brazil, Germany, Spain, Russia and Qatar. He made seven appearances for the Brazil national team and was selected for the 2001 Copa América and the 2003 CONCACAF Gold Cup, finishing as runner-up in the latter.

Three years after his retirement, The Versed wrote a report in 2017 about Ewerthon: "he was a forgotten entity on the continent, but for a while at the start of the millennium, he looked destined for the top. Sadly, as is the case with a fair number of South American migrants, he faded into footballing obscurity".

Born in São Paulo, Brazil, Ewerthon began his career at Brazilian club Corinthians in 1999, where he made thirteen appearances and scoring three times. Around at some point in 1999, Ewerthon was loaned out to Rio Branco, where he scored eight times in twenty-eight appearances. At the end of the 1999 season, he helped the side win both Brasileirão and Campeonato Paulista.

In the 2000 season, Ewerthon formed a striking partnership with Luizão. Despite suffering an injury around August, he returned to the starting lineup the following month. He helped them win the FIFA Club World Championship. At the end of the 2000 season, Ewerthon made twenty-two appearances and scoring eight times in all competitions.

At the start of the 2001 season, Ewerthon scored twice in a 5–0 win over Santos on 18 March 2001. He continued to be in a first team regular, playing in the attacking position. By the time of his departure, Ewerthon made sixteen appearances and scoring seven times in all competitions.

Despite his young age, he impressed many fans and pundits in Brazil and attracted the attention of European clubs.

Borussia Dortmund were one of the clubs chasing his signature, and on 22 September 2001, Ewerthon signed for the club, signing a five–year contract. The move reportedly cost €7.5 million.

Ewerthon made an immediate impact on his Borussia Dortmund debut when he scored and set up a goal for Jan Koller, who in return set up a goal for him, as Borussia Dortmund won 2–1 against St. Pauli on 29 September 2001. In a follow–up match against Borussia Mönchengladbach, Ewerthon set up the club's first goal of the season before earning himself a scoresheet in a 2–1 win over Borussia Mönchengladbach. Since joining the club, he quickly became a first team regular under the management of Matthias Sammer. Ewerthon then scored three goals in three matches between 17 November 2001 and 1 December 2001. Later in the 2001–02 season, his goals helped the club secure the Bundesliga title for the sixth time in their history. During the UEFA Cup campaign, Ewerthon scored two times in the knockout stage against Lille and Slovan Liberec. In the first leg semi-final of the UEFA Cup, Ewerthon set up two goals during the match in a 4–0 win over AC Milan. Despite losing 3–1 in the second leg, they reached the UEFA Cup final and played in the UEFA Cup Final which Dortmund lost 3–2 to Feyenoord at their opponents' De Kuip ground in Rotterdam. After the match, German newspaper Kicker said about his performance: “Did not enter the game at all, offensively without effect, was replaced. The only sign of life: When he initiated the counterattack, which led to the penalty.” At the end of the 2001–02 season, Ewerthon went on to make thirty-four appearances and scoring twelve times in all competitions.