I report an action research study that aimed at improving Thai pre-service teachers' understanding of the relationship between science and religion and at assisting them to respond to this issue in a science classroom. The participants were twelve post-grad students pursuing Master of Art in Teaching Science at Kasetsart University. They took a course, Philosophy of Science, taught by the researcher in Semester A, academic year 2007. Process drama is the teaching strategy employed. The students were fully engaged in the process drama; doing research, producing, distributing, and criticizing the drama. Focus group, student journal, and observation were used to gather the data and the data was analyzed using qualitative analysis techniques. The focus groups revealed that the drama could help students reflect on the complexity and sensitivity of the issue. They found there was no inherent conflict between science and religion since they answered different questions and used different methods to achieve their results. However, the conflicts occurred when people were not aware of the basic differences between the two so they justified one on the basis of purpose and method of one another. The pre-service teachers also found consistency between science and Buddhism. They thought that the teachers of science should respond to the conflicts in a respectful, compromising, and neutral manner.