Background: Despite vaccinations' efficacy in combating disease, people's readiness to get the coronavirus disease 2019 (COVID-19) vaccine are substantially varied. This study aimed to assess Vietnamese people's readiness, attitudes, and determinants for COVID-19 vaccination. Methods: A web-based cross-sectional online survey was conducted using a convenience sampling approach. The Vietnamese population's readiness to receive COVID-19 vaccinations was assessed using the 7C of vaccination readiness scale (7Cs). The scale was posted on Facebook and Zalo platforms. Descriptive statistics were calculated, and inferential analysis was applied to identify determinants predicting respondents' vaccine readiness. Results: Of the 1086 respondents invited to the study, 1026 completed the questionnaire. The Vietnamese population demonstrated a moderate level of readiness for COVID-19 vaccination uptake, with an average 7Cs score of 103.25±15.13. A high level was underscored in the complacency, constraints, collective responsibility, and compliance components, and a low level was reported in the calculation component. The Vietnamese population emphasized that the awareness of the significant adverse effects of COVID-19 vaccination was the primary factor influencing their readiness to get the vaccine (p < 0.001). Worrying about the vaccine manufacturer and its origin was the second most crucial factor influencing their readiness to get the vaccine (p < 0.001). Conclusions: Building confidence between people and the Vietnamese authorities is a high priority to enhance people's readiness to get the COVID-19 vaccine. The authorities should focus on dispelling disinformation posted on social media and promoting the usefulness of COVID-19 vaccines.