This study aims to develop an Assistive Technologies Usage Skills Assessment Scale (ATUSAS) that measures teacher candidates' assistive technologies usage skills. This study group consists of 510 teacher candidates' (282 female, 228 male). The scale's validity and reliability were statistically tested by computing the KMO and Bartlett tests, and via an exploratory factor analysis, descriptive statistics, Cronbach's alpha, a confirmatory factor analysis. As a result of the exploratory factor analysis, a construct consisted of 20 items, and three factors have been attained. The confirmatory factor analysis results have shown the adjustment to the sample that the scale applied to is at a reasonable level. The ATUSAS's Cronbach's alpha internal consistency reliability coefficient has been found as 0.90 for factor 1, 0.89 for factor 2, 0.73 for factor 3, and 0.92 for the whole test. The results show that ATUSAS is a valid and reliable measurement tool.