Vittaya Samrej (born 18 February 1964) is a Thai tennis coach and former professional player. As of 2020 he is team captain of Thailand's Davis Cup team.
Samrej had a record 18-year long Davis Cup career playing for Thailand, featuring in 37 ties between 1985 and 2002, mostly as a doubles specialist. He won 21 doubles rubbers in total, which is a former Thai record. His two singles wins both came in a 1997 tie against Hong Kong.
A regular participant in the Southeast Asian Games, Samrej has won numerous medals, including three doubles gold medals. He won a further four gold medals for his country in the team event.
Samrej won a team bronze medal at the 1986 Asian Games, then a mixed doubles bronze at the 1990 Asian Games.
His son, Kasidit Samrej, is a Davis Cup player for Thailand.