Roman Vajs (born 18 November 1974 in Liptovský Mikuláš)[1] is a retired Slovak slalom canoeist who competed at the international level from 1990 to 2004, specializing in the C2 discipline.

Vajs won two medals in the C2 team event at the ICF Canoe Slalom World Championships with a silver in 1999 and a bronze in 1993.

He also won 3 medals at the European Championships (1 gold, 1 silver and 1 bronze).

His partner in the C2 boat until 2000 was Roman Štrba, who was paralyzed in an accident in March 2001.

In the years after Štrba's accident, Vajs teamed up with Pavol Hric who had competed in K1 until then.