The effects of age of acquisition and native language prosody on the acquisition of English stress patterns were investigated with early and late Korean-English bilinguals (n = 20). Distributional patterns of stress placement based on syllabic structure, distributional patterns of stress placement based on lexical class, and stress patterns of phonologically similar words were investigated for their effect on the placement of stress in English nonwords. Both bilingual groups--like the native English controls--showed extension of stress patterns from phonologically similar real words. The effect of syllabic structure for early bilinguals was slightly different from that of native speakers, and late bilinguals showed more reduced effects. Unlike previous work with Spanish-English bilinguals, Korean-English bilinguals demonstrated a nonnativelike effect of lexical class, most pronounced in the late bilinguals. This difference might be due to Koreans' low sensitivity to word-level statistical distributions because of early exposure to a phrase-level prosodic system.