The issue of teachers' efficacy is of importance as teacher preparation programs throughout the world attempt to address shortages of qualified, competent teachers. In the field of science education, monitoring and reacting to the issue of efficacy seems to be one way in which teacher preparation programs are evaluating the structure of programs. The study reported in this paper provides a comparison of the self-efficacy of future science teachers in two countries (one developed and one rapidly developing). The purpose of the study is to compare preservice elementary teachers' efficacy beliefs at a large Turkish university and at a large American university located in the Midwest. The data for this study were collected by utilizing Enochs and Riggs' (1990) Science Teaching Efficacy Belief Instrument (STEBI-B). The STEBI-B is comprised of two subscales; personal science teaching efficacy beliefs (PSTE, 13 items) and science teaching outcome expectancy (STOE, 10 ITEMS). The participants consist of a Turkish sample of 100 preservice elementary teachers and an American sample of 79 preservice elementary teachers. The data were collected by convenient sampling. A descriptive analysis of student data indicates generally positive self-efficacy beliefs regarding science teaching in both countries. Results from this study indicate that there were differences in personal teaching efficacy beliefs of the USA and Turkish samples of preservice teachers. In general, USA preservice teachers have stronger personal science teaching efficacy beliefs than Turkish preservice elementary teachers. (Contains 4 tables.)