Can young students' early reading abilities in their first language (L1) predict later literacy development in a second language (L2)? The cross-language relationships between Chinese (L1) and English (L2) among 87 Hong Kong students were explored in a longitudinal study. Chinese word-reading fluency, Chinese rapid digit naming, and Chinese rhyme awareness at age 7 (grade 1), with age and IQ taken into account, were significant concurrent and longitudinal predictors of English word reading, and text-level reading and writing skills across ages 7-10. These three Chinese measures together accounted for 16-28% of unique variance in the English literacy tasks across the three-year period. Students who showed word-reading difficulties in Chinese in grade 1 also performed more poorly than average Chinese readers in English reading and related cognitive tasks later on, especially on phonological tasks. The results provided evidence for the cross-language transfer of cognitive-linguistic abilities between two distinctly different orthographies. L1 markers underlying reading difficulties in both L1 and L2 can serve as early indicators of possible reading problems that may arise later in L2. These findings have clinical, educational, and theoretical implications.