Silent reading fluency has received limited attention in the school-based literatures across the past decade. We fill this gap by examining both oral and silent reading fluency and their relation to overall abilities in reading comprehension in fourth-grade students. Lower-level reading skills (word reading, rapid automatic naming) and vocabulary were included in structural equation models in order to determine their impact on reading fluency and comprehension. Results suggested that oral and silent reading fluency represent separate constructs, but only oral reading fluency contributed to reading comprehension. Vocabulary was found to contribute uniquely to comprehension even after controlling for reading fluency.