Viktor Kadler (born 11 January 1981 in Győr), is a Hungarian sprint canoer.

He won his first major international title in 2004, becoming European champion as a member of Hungary's victorious four-man (K-4) kayak crew in the 200 m final.

In 2005 the Hungarians did the double, retaining their European title and then winning the World Championship final in Zagreb.

The foursome would win gold at the 2007 world championships.

Kadler is a member of the Győri VSE club.