A growing body of literature has provided evidence of the contribution of various metalinguistic skills to children's English literacy development; however, most of the studies focused on reading outcomes while spelling outcomes have been under-researched. Further, very few studies have been conducted to investigate if the results based on native English speakers can be generalized to speakers of other languages who are learning to read and spell in English. In this study, the simultaneous influence of phonological, morphological and orthographic knowledge that may impact English spelling acquisition, among Chinese students learning English as a foreign language in Grade 8 (n = 339) in mainland China and native English-speaking students in Grade 3 (n = 166) in the United States, was investigated. Measures in English tapping into the three aspects of metalinguistic skills--phonological awareness (PA), morphological awareness (MA) and orthographic awareness (OA)--were administered to both groups. Multi-group structural equation models were used to compare models between the Chinese and the American group. Results showed that 1) the overall model of metalinguistic skills predicting spelling outcome was highly similar between the American and the Chinese groups; 2) metalinguistic skills were correlated and worked in concert to compose the linguistic repertoire construct which concurrently predicted the spelling outcome; 3) MA was the major component, compared to PA and OA, of Linguistic Repertoire (LING) across the two groups. Linguistic repertoire explained 64.1% and 40.2% of the total variance in the spelling outcome for the American and the Chinese groups, respectively; and 4) the contribution of OA was greater in the Chinese group than it was in the American group, whereas the contribution of PA was greater in the American group than it was in the Chinese group. This study highlights the important contribution of MA to literacy development among both the American students and the Chinese students. It also sheds light on the influence of first language (L1) orthography on English literacy acquisition. That OA contributed more than PA to the LING construct may reflect that the English learners with L1-Chinese background have enhanced visual-orthographic processing skills. This study challenges phase models of literacy development that claim MA only contributes to literacy acquisition late in the process and offers some empirical evidence to support the emerging "linguistic repertoire" theory of literacy development. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]