In 1982, after completing his studies, Johannes Fritzsch was appointed second Kapellmeister at the Volkstheater in Rostock. In 1987 he accepted the position of Kapellmeister with the Staatsoper Dresden, Semperoper, where he conducted more than 350 opera and ballet performances over five years. After the German reunification, Johannes Fritzsch was able to accept engagements outside of Eastern Europe. In 1992–3 he worked as first Kapellmeister at the Staatsoper Hannover. He was appointed Chief Conductor and Artistic Director at the Städtische Bühnen in Frankfurt am Main and the Philharmonisches Orchester in Freiburg, where he remained until 1999 and enjoyed widespread acclaim.
Johannes Fritzsch has performed with many orchestras, both within Germany and internationally, including the Hamburger Symphoniker, Düsseldorfer Symphoniker, Philharmonie Essen, Nationaltheater-Orchester Mannheim, Staatskapelle Schwerin, Berliner Sinfonie-Orchester, Staatskapelle Dresden, Norddeutsche Philharmonie Rostock, Staatsorchester Halle, the Swedish Radio Symphony Orchestra, the Norwegian Radio Orchestra, the Danish National Symphony Orchestra, the Orchestre philharmonique de Strasbourg, the Orchestra national de Montpellier, the Orchestra national du Capitole de Toulouse, the Sydney, Melbourne, Tasmanian, Queensland and West Australian symphony orchestras and Orchestra Victoria.
Opera companies with which he has worked include Sächsische Staatsoper Dresden, Opernhaus Köln, Deutsche Oper Berlin, Komische Oper Berlin, Opera Bastille Paris, Grazer Oper, the Royal Opera Stockholm, Malmö Opera, and Opera Australia in both Sydney and Melbourne (where productions included Wozzeck, Don Giovanni, Carmen, Tosca, Rigoletto, Salome and Der Rosenkavalier).
Johannes Fritzsch has also held the position of Chief Conductor of the Grazer Oper and Grazer Philharmonisches Orchester, Austria; and from 2008 to 2014 he was Chief Conductor of the Queensland Symphony Orchestra and has since been appointed Conductor Laureate.