The present study examined the components of oral reading fluency (ORF) via various indices and their relationships with comprehension and learner-perceived difficulty of oral reading among Chinese second language (L2) learners. One hundred participants read aloud paragraphs, completed the comprehension test, and rated the difficulty of the oral reading task. Nine indices were generated to measure ORF: the percentage of omissions, substitutions, repetitions, insertions, self-corrections, and segmental problems out of the total produced characters, the number of pauses per minute, the number of actually produced characters per minute, and the number of correctly read characters per minute. The results showed that the nine indices tapped the accuracy, speed, chunking, and monitoring components of the ORF construct. The accuracy, speed, and chunking dimensions effectively predicted comprehension and the accuracy and speed dimension was closely related to learner-perceived difficulty. These findings suggested that ORF is a multi-faceted construct and can be used to assess comprehension and detect learner difficulty in Chinese L2 reading.