is a Dutch professional footballer who plays as a winger or midfielder for Première Ligue club Paris Saint-Germain.

Martens began her professional career playing for Dutch, German and Belgian clubs relatively close to her hometown of Bergen, Limburg. In 2015, Martens broke out on the international stage when she scored the Netherlands’ first ever goal in a Women's World Cup against New Zealand. In 2016, Martens’ performances at Swedish club FC Rosengård attracted the attention of FC Barcelona, who signed her the following year. Weeks after her signing at FC Barcelona was made official, Martens participated in the Netherlands' 2017 UEFA Women's Euro campaign. She was the Netherlands' standout player at that year's Euro, where the Dutch won their first ever major international title with the women's national team. She was chosen as Player of the Tournament, and later in 2017, she was voted as The Best FIFA Women's Player as well as the UEFA Women's Player of the Year.

In 2018, Forbes ranked Martens Number 22 in their \"Most Powerful Women in International Sports\" list. In the 2018–19 season, Martens helped FC Barcelona to their first ever UEFA Women's Champions League final, where she assisted their only goal in a 4–1 defeat to Olympique Lyonnais. Months later, she played in the 2019 FIFA Women's World Cup, where she fought through a toe injury for most of the tournament. The Dutch reached the final and were defeated by the United States.

In 2021, Martens was an essential part of FC Barcelona Femení completing their first continental treble, winning the UEFA Women's Champions League, the Primera Division, and the Copa de la Reina all in the same season.