She went to a grammar school which specializes in natural sciences (Realgymnasium) in Laa an der Thaya.

Mikl-Leitner taught at the business school (Handelsakademie) in Laa an der Thaya, where she had previously studied, from 1989 until 1990.

Subsequently, she became a trainee with the Federation of Austrian Industries until 1993 and then worked for a publishing company until 1995.

Johanna Mikl-Leitner was a member of Austria's national council from 29 October 1999 (1999-10-29) until 18 April 2003 (2003-04-18), representing the ÖVP.

[1] After the resignation of vice chancellor and ÖVP party leader Josef Pröll, the Faymann cabinet was reshuffled and Johanna Mikl-Leitner was sworn in as Austria's minister of the interior on 21 April 2011.