The lead singer or lead vocalist of a band is the member who sings the main portions of a song. In some occasions, the lead singer may also play one or more instruments. Often, the lead singer is seen as the "leader" as well as the spokesman of the band to the public.
Petra has had two official lead singers through its career. However, other members have also shared lead vocal duties from time to time.
These are the lead singers of Petra through its trajectory.
- Bob Hartman and Greg Hough – 1972 to 1977
- Greg X. Volz – 1978 to 1985, 2010 to 2012 with Classic Petra
- John Schlitt – 1986 to present
Other official members that have shared lead vocal duties within the band are:
- Rob Frazier – Shared lead vocals with Volz from 1978 to 1979
- Mark Kelly – Shared lead vocals with Volz on the song "Disciple" (1982)
- Pete Orta – Sings lead vocals on the song "Breathe In" (2000)