The reciprocal influences between the development of Chinese-as-a-second-language (CSL) listening and reading comprehension among young learners in Hong Kong were evaluated using a 2-year, three-wave longitudinal design. A total of 129 senior primary CSL students were assessed using listening and reading comprehension tests at the end of grades 4, 5, and 6. An autoregressive, cross-lagged model was specified, and it accounted for a substantial portion of variance (more than 60%) in the two comprehension abilities by grades 5 and 6. Path analysis showed that the two comprehension abilities facilitated each other's development across the years: on controlling for their respective strong autoregressive effects, the two comprehension abilities predicted a unique, substantial variance portion of each other every year. In addition, based on previous studies conducted on readers of both alphabetic languages and Chinese, this study argues the following points: (1) the development of CSL students' reading comprehension is constrained by their listening comprehension, and (2) the acquisition of Chinese literacy skills may promote students' listening comprehension by enhancing their linguistic knowledge and awareness.