In recent education reform policies of different countries, scientific literacy was set as the national goal for science education. Understanding how science itself and scientists really work, in other words, understanding the nature of science is necessary to reach the desired scientific literacy level. Students also need to understand the components of nature of science such as scientific inquiry to reach that literacy level. The nature of science is also a useful tool to change teachers' views of learning and teaching. Brickhouse (1989) argues that how teachers perceive teaching and learning and how they really teach are influenced with their understanding of the nature of science. Specific instructional behaviors, activities, and decisions implemented within the context of a lesson are the most important variables that influence students' understanding of the nature of science. Therefore, teachers themselves need to have adequate understanding of the nature of science. For this study a cohort of 24 pre-service elementary teachers enrolled in elementary science methods course at a large Northeastern University served as research participants. This study examined pre-service elementary teachers' understandings of the nature of science-scientific inquiry and its role in school science via document analysis. Findings of this research illustrated that pre-service teachers understanding of nature of scientific knowledge became centered on perceptions about scientific inquiry. That is, they perceived scientific inquiry as a means to add more products to existing body of scientific knowledge. In conclusion, the prospective elementary teachers in this study perceived that both scientists and learners use scientific inquiry in the development of scientific knowledge.