The acquisition of reading vocabulary is one of the major challenges for deaf children in bilingual education programs. Deaf children have to acquire a written lexicon that can effectively be used in reading. In this paper, we present a developmental model that describes reading vocabulary acquisition of deaf children in bilingual education programs. The model is inspired by Jiang's model of vocabulary development in a second language (N. Jiang, 2000, 2004a) and the hierarchical model of lexical representation and processing in bilinguals (J. F. Kroll & E. Stewart, 1988). We argue that lexical development in the written language often fossilizes and that many words deaf readers acquire will not reach the final stage of lexical development. We argue that this feature is consistent with many findings reported in the literature. Finally, we discuss the pedagogical implications of the model.