The main aim of this study was to determine the teaching practices of prospective high school physics teachers with respect to their preference for teaching as a traditionalist or as a constructivist. To study the beliefs of prospective high school physics teachers on this subject, firstly, the Teacher Belief Survey was administered to 135 prospective high school physics teachers; and then semi-structured interviews were conducted with eleven prospective high school physics teachers. Analyzing of the survey and interviews showed that most prospective high school teachers had intermediate (traditionalist to constructivist) beliefs about teaching physics.