Ernst Oestreicher has been principal of the Berufsfachschule für Musik Bad Königshofen since March 1989, where he teaches ensemble conducting. He studied music teaching at the HfM Würzburg (piano with Prof. Julian von Karolyi, trumpet with Prof. Adolf Pfister) and trumpet (Prof. Helmut Erb).

Since 1976, in addition to his professional activities, Oestreicher has been intensively involved in the field of wind orchestras and has led a number of successful wind orchestras to date. In 1988, he was elected Federal Conductor of the North Bavarian Music Association and, between 1986 and 1990, established an advanced training system for amateur wind musicianship and conducting. He played a leading role in the redesign of the instrumental performance examinations D1, D2 and D3. Since 1988, he has been a regular jury member at important competitions for wind orchestras, even abroad.

From 1987 to 2001, Oestreicher played a major role in the conception of the German Orchestra Competition as a member of the main committee. From 1998 to 2001 he was Federal Music Director of the BDBV and in this capacity had the musical direction of the 3rd German Federal Music Festival. In 2005 he was elected to the board of the Bavarian Academy in Hammelburg. Since 2005, he has also been a member of the Presidium of the Bavarian Music Council and, since 2010, Vice President of the Federal Association of German Music Associations.

Oestreicher currently conducts the Symphonic Wind Orchestra of the City of Volkach and the North Bavarian Youth Wind Orchestra. He has enjoyed significant success with both ensembles, including winning the 2010 German Selection Orchestra Competition in Bamberg.