Johannes Sebastian Polgar (born 25 August 1977) is a German sailor, who specialized in the multihull (Tornado) and keelboat Star) classes.

[1] Together with his partner Florian Spalteholz, he was named one of the country's top sailors in the mixed multihull catamaran for the 2008 Summer Olympics, finishing in eighth place.

[2] After the Games, Polgar decided to move into the Star class and eventually shared a gold-medal victory with his partner Markus Koy at the 2010 Europeans in Viareggio, Italy.

Leading up to their maiden Games, he and crew member Spalteholz topped the selection criteria in a duel against brothers Tino and Niko Mittelmeier for the country's Tornado berth, based on their cumulative scores attained at two international regattas stipulated by the German Sailing Federation (German: Deutscher Segler Verband).

[6][7] An unforeseen capsize by the German duo on the initial run, however, saw their medal chances vanish, plummeting them further to eighth overall with 74 net points.