Marta Xargay Casademont (born 20 December 1990) is a Spanish professional basketball player. She plays for Phoenix Mercury of the WNBA, USK Praha and Spain women's national basketball team. She has represented national team since EuroBasket Women 2011 competition. She won EuroLeague Women 2010–11 with Perfumerías Avenida Baloncesto. She left Spain in 2015, joining both USK Praha of the Czech League in 2015 and the Phoenix Mercury of the WNBA on 11 February 2015. In September 2018 she signed for Dynamo Kursk of the Russian Premier League.
Xargay started playing basketball from a young age in clubs in her hometown Girona, entering the youth levels of Uni Girona CB at 14 and making it to the senior team and the Spanish second tier. In 2009 she signed for CB Avenida from Salamanca, where in the following six seasons she won two leagues, three cups and one EuroLeague.
During 2015 and 2016 she played both in the WNBA with Phoenix Mercury and the European season with USK Praha, where she won the 2016, 2017 and 2018 Czech League. Due to her commitment to the Spain national team, she opted not to play in the WNBA in 2017 or 2018. In 2018 she signed for Russian team Dynamo Kursk.