The nature of the relation between orthographic knowledge and vocabulary in second language (L2) English learners remains relatively unclear. The current study investigated how orthographic knowledge facets, as well as morphological awareness, were concurrently related to vocabulary knowledge. A group of 241 eighth-grade Chinese learners of English as a foreign language (EFL) were administered measures of phonological awareness, orthographic knowledge (lexical and sublexical orthographic knowledge), morphological awareness (morpheme recognition and morpheme discrimination), and vocabulary knowledge. Drawing on structural equation modeling analyses with phonological awareness controlled, the study found that orthographic knowledge was associated with Chinese EFL vocabulary knowledge directly and indirectly through morphological awareness. It was also observed that lexical orthographic knowledge had a stronger indirect effect on vocabulary knowledge; however, sublexical orthographic knowledge had a more significant direct effect on vocabulary knowledge. These results inform current theories of reading development as applied to L2 English reading. (c) 2025 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.