Although a major goal of Science, Technology, Engineering, and Mathematics (STEM) education is to develop scientific literacy, prior efforts at measuring scientific literacy have not attempted to link scientific literacy with success in STEM fields. The current Scientific Literacy Survey for College Preparedness in STEM (SLSCP-STEM) scale was specifically developed to predict the academic preparedness of incoming freshman STEM majors. The SLSCP-STEM was developed within the context of utilitarian scientific literacy and allows independent assessment of three dimensions of scientific literacy: (a) attitudinal and behavioral domains of scientific literacy, (b) content knowledge of scientific concepts, and (c) scientific reasoning skills. This paper presents the theoretical framework for the development of the scale along with supporting data on its validity and reliability. The SLSCP-STEM demonstrated reliability including tests of internal consistency [attitude/behavior dimension (α = .86), content knowledge dimension (α = .73), scientific reasoning dimension (α = .72)] and instrument stability over time [attitude/behavior dimension (r = 0.88, p < .01), content knowledge dimension (r = 0.74, p < .01), scientific reasoning dimension (r = 0.80, p < .01)]. Furthermore, content validity, tested with expert science faculty members, demonstrated that the content knowledge sections were relevant for freshman STEM majors. Finally, item analysis verified appropriate item difficulty level and item discrimination.