This study assessed the reading motivation of 133 students at individual grade levels (2nd-5th), who were divided in subgroups with and without reading disabilities/difficulties (RD) and with and without attention deficit hyperactivity disorder (ADHD). Major findings were that students in the RD subgroup had lower reading motivation (intrinsic, extrinsic, and self-efficacy) and read less for enjoyment than the nondisability (ND) group; students in the combined group (ADHD + RD) showed these motivational deficits in earlier grade levels. However, students with ADHD did not differ from the ND group in reading motivation, and children with RD (with and without ADHD) were equivalent to ND in social motivation up to the 5th grade. Implications of these findings were (a) social reading is an instructional pathway for both groups of students with RD, (b) assessments of reading motivation, in addition to reading skill, may be important in assessing responses to intervention, and (c) motivational interventions should be implemented early before motivational responses become a motivational style. (Contains 6 tables and 2 figures.)