Sthefany Thomas Díaz (born 4 May 1989) is an Argentine basketball player who plays as a forward. She has been a member of the Argentina women's national team at under–18 (2006), under–19 (2007) and senior (2008–2016) levels. She is the daughter of Jim Thomas, an American former basketball player, and an Argentine mother. She was born in Temuco, Chile, while his father was playing there. She was initially raised in Argentina and then in the United States. She attended the Clemson University. Her brother Erik Thomas is also a basketball player.