The factor structure and reliability of an instrument for measuring attitudes of preservice teachers toward science were studied as part of a 5-year project at the University of Wyoming (Laramie) to improve the teaching of science at the elementary school level. The Attitudes towards Science and Scientists Scale (ATSSS) of J. R. Cummings (1969) was administered to preservice elementary school teachers in 1989 and 1990. The ATSSS consists of 67 Likert-type items intended to measure seven facets of attitudes about science. Items for a revised scale were chosen based on factor analyses and the results of item analysis. The revised version, the Inventory of Science Attitudes (ISA), was administered to 72 preservice elementary education majors taking mathematics, science, and music methods courses over the summer session in 1990. Factor analyses and measures of reliability indicated that the revised version was more valid and reliable than was the ATSSS. Two tables present the rotated factor pattern for Promax rotation and the distribution of scores on the ISA. The 30-item ISA is included. (SLD)