Karl Komzák (* November 8, 1850 in Prague ; † April 23, 1905 in Baden bei Wien (Vienna), Austro-Hungarian Empire) was an Austrian-Czech composer.
Karl (actually Karel) Komzák was born on November 8, 1850 in Prague. His father, Karl Komzák Sr., recognized his son's talent at an early age and taught him music theory.

Komzák studied from 1861 until 1867 at the Prague Conservatory violin under the direction of Moritz Mildner and Anton Bennewitz. He worked afterwards in his father's orchestra and became the second music director of the ''Linzer Landestheater'' (Linz State Theater). During the end of 1871 he assumed the position of music director at the ''k.k. Landwehr-Infanterieregiment Nr. 7 Baron Maroicic'' in Innsbruck and also directed the ''Innsbrucker Liedertafel'' in which he became an honorary member.

Komzák married Eugenie Reichardt in 1877 in Innsbruck. Her father was Johann Reichardt, a retired artillery lieutenant colonel and as of July 1888 he was elevated to a higher social position with the title ''Reichhardt Edle von Hardtland''. He died on December 14, 1923, in Baden bei Wien (Vienna) at the age of 66 or 67.

As of 1883, Komzáks was the music director of the 84th Infantry Regiment in Vienna, an orchestra which under Karl Komzáks conducting received nationwide recognition and was premiered as ''the best of all military bands in the world'' at the Paris World Exposition in 1889.

Komzák composed in 1890 by commission of the '' k.u.k. Kriegsministeriums'' (Austro-Hungarian Ministry of War) a new version of the national anthem (later Federal anthem) with text by Ottokar Kernstock. In 1898, he won first prize among 92 entries in the composition contest for the ''Kaiser-Franz-Josef-Jubiläumsmarsch'' (op. 260).

Komzák was an honorary member of various music associations and possessed national and international awards (including from Serbia, Turkey, Montenegro and Persia).

The public was always fond of Komzák as he had a sympathetic charm and a friendly character. Karl Komzák relocated to Baden where he took over the direction of the ''Kurorchestra'' (Spa Orchestra) on April 26, 1893 which had been vacant for a year. Initially it was a two year contract which allowed him during the winter to be available to his regiment which had been transferred to Mostar, Bosnia and Herzegovina (otherwise he was in a furlough status). In 1896 he was separated from the military.

In the first years he formed his own orchestra with the help of his archivist and horn player Georg Müller. Later the ''Wiener Konzertverein'' (Vienna Concert Association) came to Baden for the summer season. Komzák also conducted the popular concerts in the ''Wiener Großen Musikvereinssaal'' (Vienna Great Musical Association Hall) and was on tour. During this period originated his most famous work '' The Bad’ner Mad’ln Waltz''.