Rafael Duailibe Leitão (born 1979 in São Luís, Maranhão) is a Brazilian chess grandmaster. He won the World Youth Chess Championship in the U12 category in 1991 and in the U18 category in 1996. He won the Brazilian Chess Championship in 1996, 1997, 1998, 2004 and 2011 and played for Brazil in the Chess Olympiads of 1996, 2000, 2002, 2006 and 2010.
He is currently playing in the 26th World Correspondence Chess Championship, which began in the summer of 2010.
His username on the Internet Chess Club is "Pigzilla".