<p>Morphological awareness is a critical predictor of reading comprehension, yet its direct and indirect contributions within and across languages remain complex in bilingual children, particularly in typologically distinct language pairs. We examined pathways from morphological awareness to reading comprehension within and across first language (L1) Chinese and second language (L2) English in Chinese-English bilinguals. A cross-sectional sample of 467 Hong Kong students in Grade 2 (<i>n</i> = 150, age = 8.10 years), Grade 5 (<i>n</i> = 158, age = 11.19 years), and Grade 8 (<i>n</i> = 159, age = 13.79 years) completed measures of morphological awareness, vocabulary, word reading, and reading comprehension in both L1 and L2. Grade-specific structural equation models showed that L1 morphological awareness predicted L1 reading comprehension indirectly via vocabulary in Grade 2, but directly in Grades 5 and 8. L2 morphological awareness predicted L2 reading comprehension directly and indirectly via vocabulary and word reading in Grade 2, directly in Grade 5, and directly and indirectly via vocabulary in Grade 8. Across languages, L1 morphological awareness supported L2 reading comprehension through L2 morphological awareness, vocabulary, and word reading and L2 morphological awareness supported L1 reading comprehension through L1 morphological awareness and vocabulary in Grade 2. By Grade 5, there was an indirect pathway from L1 to L2 via L2 morphological awareness. In Grade 8, significant indirect effects emerged bidirectionally via morphological awareness in the other language. Findings reveal a dynamic role of morphological awareness in bilingual reading comprehension, highlighting the need for grade-tailored, language-general and language-specific morphological instruction in literacy support for bilingual children.</p>