Carl or Karl Heissler (18 January 1823 – 13 November 1878) was an Austrian violinist and violist.

He studied with Joseph Hellmesberger, Sr., Matthias Durst and Joseph Böhm at the Academy of the Vienna Music Friends Society.

Heissler taught at the Vienna Conservatoire, where his students included Julius Winkler, Arnold Rosé, Hans Wessely and Franz Schalk.

He was the first Director of the orchestral association of the Gesellschaft der Musikfreunde (1869) in Vienna.

[1] His successor was Anton Rubinstein (1871), followed by Johannes Brahms (1872).