António Santos Fernandes is a Portuguese chess grandmaster and a lawyer by profession. He was born on 18 February 1962 in Lisbon, Portugal. Fernandes first learned how to play chess at 15. He won the Portuguese Chess Championship in 1986, 1990, and 1991 and became a FIDE International Master in 1995.

In 1993, he earned the country's individual championship. He had also won national championships in 1986, 1990, and 1991, and was a member of the national team in various chess competitions. He represented Portugal internationally, including participation in the Chess Olympiads.

He was awarded the title of International Grandmaster in February of 2003. He became the first-ever Portuguese player to acquire the Grandmaster title. Nevertheless, Fernandes is simultaneously practicing law and continuing his involvement with chess.

António Fernandes is also the author of various chess books. He published a chess book named Xeque-Mate in 1983 and he also issued two booklets which contained his games between 1988 –1992 and 1993–1994, respectively.