This study employed a large-scale cross-sectional survey (n = 443) to develop and validate second language (L2) regulatory styles [Noels et al. 2000. "Why are You Learning a Second Language? Motivational Orientations and Self-Determination Theory." "Language Learning" 50 (1): 57-85] in the sample of successful English learners in an English as a second language context. Confirmatory factor analysis was used in this study to test five different models and the preferred model identified as many as six factors of regulatory style (i.e. intrinsic knowledge, intrinsic accomplishment, integrated regulation, identified regulation, introjected regulation and external regulation) in that context. Integrated regulation was the most endorsed factor among all regulatory styles, and it had a medium correlation with identified regulation. Different from Noels and her colleagues' proposition [Noels, Clément, and Pelletier 2001. "Intrinsic, Extrinsic, and Integrative Orientations of French Canadian Learners of English." "Canadian Modern Language Review" 57 (3): 424-442] that it was hard to differentiate integrated regulation from identified regulation, the findings of this study suggest otherwise, and L2 regulatory styles would do well to extend its scope to allow for integrated regulation as a separate entity. Thus, foreign language teachers are expected to help students internalise the behaviour of this foreign language learning into their own goals or needs. That behaviour contributes to an individual's psychological well-being [Ryan and Deci 2000. "Self-Determination Theory and the Facilitation of Intrinsic Motivation, Social Development, and Well-being." "American Psychologist" 55: 68-78] and then contribute to an ideal L2 self. Introjected regulation was rejected, signifying that successful L2 learners need more autonomous motivation to be high achievers. Therefore, it is suggested that the specifics of a language proficiency group and different learning contexts as well should be taken into account in the future study on language learners' motivations.