This study examined the discrimination of word-final stop contrasts (/p/-/t/, /p/-/k/, /t/-/k/) in English and Thai by 12 listeners from diverse Asian language backgrounds (e.g., Cantonese, Korean, Indonesian, Vietnamese). Some of their first languages (L1) share specific phonetic realization of stops with Thai, namely, unreleased final stops and differ from English which allows both released and unreleased final stops. These 12 multilingual (M) listeners' discrimination accuracy was compared to that of the two listener groups (Australian English (AE), Thai (T), n = 18 each) tested in previous studies using the same experimental procedures. The M group did not differ from the AE or T group in discriminating English stop contrasts, but was significantly less accurate than the T group in discriminating Thai stop contrasts. They were slightly (but nonsignincantly) better than the AE listeners in discriminating Thai stops. This suggests that familiarity with specific phonetic realization of sounds (i.e., unreleased final stops) may play a facilitative role in perceptual flexibility, but without an exposure to native phonetic contrasts that include detailed acoustic characteristics, it may be difficult to develop the capacity to discriminate subtle phonetic differences to the level of native listeners.