Fritzsche was born in Bochum and served in the German army from 1917. Post-war he studied briefly at a number of universities before becoming a journalist for the Hugenberg Press and then involved in the new mass media of the radio, working for the German government. In September 1932 he was made head of the Drahtloser Dienst (the wireless news service). On May 1, 1933 he prudently joined the NSDAP. Under Joseph Goebbels' Reich Ministry he continued to head the radio department before being promoted to the News Section at the Ministry. In mid 1938 he became deputy to Alfred Berndt at the German Press Division. Responsible for controlling German news, the agency was also called the Home or Domestic Press Division. In December 1938 he was made chief of the Home Press Division. In May 1942 Goebbels took personal control of the division and Fritzsche returned to radio work for the Ministry as Plenipotentiary for the Political Organization of the Greater German Radio and head of the Radio Division of the Ministry.
Fritzsche was taken prisoner by Soviet soldiers in Berlin on May 2, 1945. He was tried before the International Military Tribunal, in place of the deceased Goebbels he was charged with conspiracy to commit crimes against peace, war crimes and crimes against humanity. He was one of only three Nazi figures to be acquitted at Nuremberg. But he was soon charged with other crimes and was eventually sentenced to nine years. He was released in September, 1950 and died of cancer soon afterwards.