Science is a basic course that improves the individuals in terms of cognitive aspects and increases their creativity. In this course, students acquire the habits of thinking objectively and making right decisions about the phenomena and events by examining their environment with scientific methods. In this process, an effort is spent to make students gain scientific knowledge, cognitive process skills and scientific attitudes. Scientific attitudes have an important role in developing scientific literacy. The purpose of this study is to bring up the results of reliability and validity studies of an instrument which is developed for determining scientific attitudes of fifth grade students. The data were collected from 887 students of randomly selected 14 elementary schools in the city of Eskişehir. As a result of factor analysis, the scale grouped in with three factors accounted for 42,08% of total variance with 28 items.