While it long has been accepted that the study of beliefs is important in understanding teacher's practices and their decision-making in the classroom, there is a growing body of research which argues that teachers' personal religious beliefs serve as the initial set of the interpretive process of gaining new knowledge. These beliefs play an integral role in producing, filtering, prioritising and interpreting information. Moreover, researchers explain that A science teacher not only presents scientific concepts, but tacitly creates a context in which scientific concepts are presented to the class. This context can be strongly influenced by teacher beliefs or worldview. World events have shown us that religion can have a profound impact on many societies and that individuals' religious beliefs can certainly influence their own actions. Therefore, religious influences on contemporary teachers' lives should be considered when building an understanding of their work in the classroom. The influence of religion on the teacher's practices will be significant especially if the teacher has to respond intelligently and effectively to the challenges of science curriculum which include some controversial issues which might take a part of the science/religion spectrum.There are many studies in the science education literature about science teacher's beliefs. Most of these studies investigate science teachers' beliefs about science and education in isolation from their religious belief system that could be the core of person belief. Most of the studies of beliefs focus on teachers beliefs about teaching/learning science or the nature of science. Also, most of theses studies have been carried out in western cultures, and not in a religiously orientated context. A new study, in this different context, may give new insights into the dynamics of the relationship between teachers' professional beliefs, personal religious beliefs and practices. Many topics included in science education are acknowledged as controversial issues, for example, evolution, cloning, abortion, and genetic engineering. These issues pose problems for science teachers, especially in a religiously based culture, because of the nature of the conflict between the implications of a scientific study of some these issues, and religion. Some other issues may not formally conflict with religion but, teachers' views or the way they interpret the religious view regarding these controversial issues can create a false contradiction which might influence their performance and in turn influence their students' learning. Therefore, there is a need to understand teachers' personal religious beliefs, and practices about some of these and the way their beliefs influence their performance in the class. This paper describes a study conducted to address these needs. The study looks at the role and influence of religion on the science teacher performance. Research questionsThe main research question is "to what extent does religion affect science teacher performance?" To answer this question, the study poses these sub-questions; 1. What are science teachers' views of the relationship between religion and science?2. Do science teachers see conflict or harmony between science and religion and why might this be so? 3. For those we see conflict between science and religion is science or religion the greater authority?4. Does science teachers' religious beliefs influence on their professional beliefs about science education? 5. Is there an influence of teacher religious beliefs on the way they teach science or on some other involvement with science education? The study adopted a constructivist perspective using an interpretive approach. The research was guided by teachers' worldviews of science, which I regarded as their socially constructed realities.100 Egyptian science teachers responded to a questionnaire to assess their personal religious beliefs about some controversial issues. After analyzing the questionnaire data, the maximum variation strategy was used to select 10 teachers. Data were collected from these 10 teachers using interviews, memos and observations.The findings highlighted the power influence of teachers' religious beliefs on dealing with or gaining with new knowledge (the epistemology and the ontology of science). Also the findings found that teachers' beliefs are among the major constructs that drive teachers' ways of thinking and classroom practices.Bausor, J. & Poole, M. (2002). Science-and religion in the agreed syllabuses-an investigation and some suggestions. British Journal of Religious Education, 25, (1), pp.18-32 Fysh, R. and Lucas, K. (1998). Religious beliefs in science classrooms. 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Journal of Teacher Education, or 5. Teaching and Teacher Education, or 6. International Journal of Science Education, or 7. Research in Science Education, or 8. Science Education