Elevated blood pressure (BP) is a growing burden worldwide, leading to over 10 million deaths each year. May Measurement Month (MMM) is a global initiative to raise awareness of high BP and act as a temporary solution to the lack of screening programmes worldwide. We aimed to screen for hypertension and cardiovascular risk factors in people aged ≥18 years in the community, thereby defining the proportion of subjects with elevated BP and assess the awareness and the effectiveness of its treatment. An opportunistic cross-sectional survey of volunteers aged ≥18 years was carried out in May 2019. Blood pressure measurement, the definition of hypertension and statistical analysis followed the standard MMM protocol. From May 2019 to June 2019, through 10 cities/provinces in Vietnam, 25 887 individuals with mean age 48.7 (SD ±17.7) years were screened. After multiple imputations, 8758 (33.8%) had hypertension. Of individuals not receiving antihypertensive medication, 3025 (15.0%) were hypertensive. Of individuals receiving antihypertensive medication, 2800 (48.8%) had uncontrolled BP. Raised BP [systolic BP (SBP) ≥140 mmHg and/or diastolic BP (DBP) ≥90 mmHg] was also associated with additional risk factors including smoking, alcohol intake, previous hypertension in pregnancy, and obesity. May Measurement Month 2019 was the most extensive BP screening campaign ever undertaken in Vietnam. Undiagnosed and uncontrolled hypertension in Vietnam remains a substantial health problem. Local campaigns applying standardized methods such as MMM 2019 will be beneficial to screen for the significant number of individuals with raised BP and increase the awareness of hypertension.