This study explored the relationships of oral reading speed and error rate on comprehension with second and third grade students with identified reading risk. The study included 920 second and 974 third graders. Results found a significant relationship between error rate, oral reading fluency, and reading comprehension performance, and grade-specific guidelines for appropriate error rate levels. Low reading fluency and high error rates predicted the level of passage comprehension performance. For both second and third grade students, fall assessment error rate predicted comprehension performance. The acceptable third grade error rate cut point was 14%. Instructional implication are discussed. (Contains 5 tables and 1 figure.)