Background: Personality disorders is one of the most assessed mental health problems among prison population. To date, no local psychometric instrument to assess personality disorder is available in Malaysia. Objective: The aim of this study is to validate the Malay-translated version of the McLean Screening Instrument for Borderline Personality Disorder (MSI-BPD) among prisoner. Methods: A cross-sectional study was designed, involving female prisoners (n=90). Face validity, factor analysis, and reliability testing were conducted with a one-week interval test-retest. Results: The translated instrument produced four factors structure. The internal consistency is moderate (α=.64), with high test-retest reliability (ICC=.82). Conclusion: The Malay-translated version of the MSI-BPD was found valid and reliable to identify borderline personality disorder among female prisoner in future studies.