ABSTRACT This study extends the Theory of Planned Behavior (TPB) by incorporating perceived knowledge of COVID-19 (PKC) and destination overall image (DOI) to explore the travel intentions of Taiwanese and Chinese tourists to Vietnam post-pandemic. Utilizing a consistent PLS multigroup analysis (PLS-MGA), it contrasts the decision-making processes between these groups. The augmented TPB framework explains 81.9% of the variance in travel intentions. Key findings indicate that PKC significantly influences TPB determinants, with a more pronounced effect on Attitude toward behavior among Chinese respondents. Attitude, subjective norm, perceived behavioral control, and DOI positively affect destination visit intention. These insights are critical for tourism marketers and policymakers in devising strategies to attract Taiwanese and Chinese tourists to Vietnam, highlighting the enhanced TPB model’s relevance in examining tourist behavior with pandemic awareness. This study paves the way for future research to further extend TPB concerning COVID-19’s impact.