<p>This study aims to validate the Modified Lay Public Stigma in the Family Stigma in Alzheimer’s Disease Scale (Modified FS-ADS) with Vietnamese general public. A sample of 135 students aged 18 to 24 completed a self-ministered survey on their attitude toward people with dementia. Exploratory principal factor analysis using varimax rotation was adopted to explore potential factors of 34 items. Using iterative process, this exploratory principal factor analysis was conducted three times, using the same criteria to retain items. Only factors with Eigenvalues &gt; 1 and associated items with factor loading &gt; = 0.5 and loaded on only one factor were retained for further examination. After the final exploratory principal factor analysis, Cronbach’s alpha of each subscale was computed to examine their internal reliability. The construct validity of the final retained subscales was evaluated using the Pearson correlation coefficients between these subscales and dementia knowledge and compassion. The validated scale retained 17 items distributed to four factors or subscales, namely: (1) perception of esthetics of, (2) willingness to help, (3) extremely negative feelings (fear and disgust) toward, and (4) social distance toward people with dementia. All subscales show high reliability. The Modified Lay Public Stigma Scale from FS-ADS is a valid and reliable instrument to assess public stigma among Vietnamese general public in their sociocultural context. The validated scale with its four subscales is not only empirical derived, but also theoretical underpinned, and therefore, importantly contributes to future studies on public stigma among Vietnamese population.</p>