The purpose of this descriptive study was to develop a computational fluency performance profile of 224 high school (Grades 9-12) students with mathematics disabilities (MD). Computational fluency performance was examined by grade-level expectancy (Grades 2-6) and skill area (whole numbers: addition, subtraction, multiplication, division; rational numbers: fractions, decimals) using the "Mathematics Operations Test-Revised" (MOT-R). The findings indicated that these high school students with MD were fluent only in computational skills at the second- and third-grade levels. Computational fluency was found with most whole number basic facts in addition, subtraction, multiplication, and division. Lack of computational fluency was demonstrated on many items dealing with subtraction of multiple digits or items requiring regrouping, most multiplication and division items, and rational number items involving fractions and decimals. The results are discussed in regard to instructional programs and curriculum organization for high school students with MD.