In this study, the relationship between bilingualism and personality shifts was explored as previous researchers have reported that switching languages can result in the shifting in one’s personality. It is estimated that more that more than half of the world’s population is bilingual, making study of this occurrence important. Several studies exploring this phenomenon have been conducted on different bilingual populations (Hong et al., 2001; Luna et al., 2008; Ramirez-Esparza et al., 2006), but less commonly on Vietnamese-English bilinguals. Given the scarcity of studies in this specific population, there is a need to explore personality shifts on Vietnamese-English bilinguals. It was hypothesized that Vietnamese- English bilinguals would experience personality shifts as the culture-related linguistic cues change. The initial finding supported the hypothesis in this study. The result from the first t-test indicated that Vietnamese-English bilinguals expressed more traits associated with the Agreeableness factor when they answered in Vietnamese, than when they did in English. However, the DIF analysis and the second t-test results suggested that the significance observed in the initial finding may be due to translation inequivalence across two versions. This inconclusive result suggested that there is a further need in future research to validate the measure on a larger sample size, and explore the phenomenon of bilingual personalities in general.