The present study aims to develop de novo scales to assess the level of knowledge of and attitude toward acquired immunodeficiency virus (AIDS) among the Turkish population. For this purpose, a 37-item knowledge scale and a 23-item attitude scale were developed and tested by using convenience sampling of undergraduate students (N = 1025) aged >= 17 years from five universities in Izmir. After evaluating item difficulty and item discrimination, 12 items were excluded, and during factor analyses, four additional items were omitted from the knowledge scale. Oblique rotation resulted in three underlying factors that explain 34% of the variance. As a reliability assessment, the Kuder-Richardson-20 coefficient was found to be .76. For the attitude scale, six items were omitted after factor analyses. Oblique rotation showed two underlying components that explained 42.43% of the variance. For internal reliability, Cronbach's alpha was found as. 90. Additionally, to test the relation between the scales, correlation analyses were performed, and it was found that the more knowledge of AIDS people have, the more positive their attitudes are toward it. As a conclusion, both a 21-item AIDS Knowledge scale and a 17-item AIDS Attitude scale have acceptable psychometric values and both can be used in future research.