Introduction Self-care behaviour is fundamental in preventing hypertension in the general population. According to the Health Belief Model, health beliefs and perceptions influence the success in adopting disease prevention strategies. While factors influencing hypertension self-care behaviour have been examined previously in patient populations, they have not been assessed in the general community. Methods This was a cross-sectional study conducted between 12 June 2020 to 26 July 2021. An online survey was administered via email and social media to Malaysians in the Selangor and Kuala Lumpur communities. Respondents were over 18 years old, without a formal diagnosis of hypertension. The survey evaluated hypertension knowledge, Health Belief Model constructs, self-care behaviour frequency, and motivators and barriers to self-care behaviour. Multiple linear regression was performed to determine the main predictors of self-care behaviour, and descriptive statistics were used to characterise motivators and barriers of each self-care behaviour. Results Only health motivations (β = 0.217, p < 0.001) and perceived barriers (β = 0.571, p < 0.001) significantly influenced self-care behaviour. Maintaining a healthy diet, regular physical activity and blood pressure checks need to be improved in the community, particularly in reducing salt and calorie intake. Lack of time, limited choices and laziness are the biggest challenges that need to be tackled in adopting a healthy diet and an active lifestyle in the community. Many are ignorant towards their health status, therefore, do not prioritize blood pressure screenings, suggesting a need to enhance community blood pressure checks for early diagnosis of hypertension. Conclusion and implications Motivations and barriers were the main determinants of self-care behaviour in the Selangor and Kuala Lumpur community. Targeting these aspects of self-care behaviour should be considered when developing interventions and education programmes tailored to local cultural, environmental and personal factors, to more effectively reduce the hypertension prevalence and burden.