The literacy development of d/Deaf and hard of hearing (d/Dhh) children has always been a matter of grave concern among educators, and grammatical knowledge is said to constitute a major component such development. The present article reports on a study that examined the development of Chinese grammar among groups of d/Dhh and hearing children who received education through a sign bilingualism and coenrollment (SLCO) approach. Findings from administration of a prestandardized assessment tool showed that while the d/Dhh children generally lagged behind their hearing peers at all levels, the gap began to narrow from Primary 2 onward, and they caught up with their hearing peers in most except for a few grammatical constructions by Primary 4. Qualitative analysis revealed a similar developmental profile and similar degrees of difficulty in mastering the more complex constructions in written Chinese between the two groups of children.