While most English words are multisyllabic, research on literacy acquisition has tended to focus on early acquisition of monosyllabic words. The processes involved in multisyllabic word reading and spelling in middle childhood are likely to differ from those in monosyllabic reading and spelling. The current paper examines the contributions of morphological awareness (MA; awareness of derivational morphemes), prosodic sensitivity (sensitivity to lexical stress), and phonological awareness (PA; awareness of phonemes) for multisyllabic word reading and spelling, after accounting for background variables (age, vocabulary, nonverbal IQ, short-term memory). Seventy 7–10-year-old children completed a battery of tasks. MA and prosodic sensitivity were independent predictors of multisyllabic reading, while MA and PA were independent predictors of multisyllabic spelling. These results contrast with previous research, which instead found that PA plays a more prominent role while prosodic sensitivity appears to demonstrate only an indirect influence. However, those studies largely examined reading of shorter, one to three syllable words. These findings indicate when words are longer and multisyllabic, prosodic sensitivity, PA, and MA have differing direct influences on literacy. MA and prosodic sensitivity relate to word reading, while MA and PA are important for spelling.