Introduction: Hypertension is one of the chronic diseases with a rising trend globally, including Malaysia. Patients' own perception of their illness is a strong factor that determines their health-seeking behaviour. The objective of this study was to evaluate the illness perception of hypertensive patients and the associated factors. Method: A cross-sectional study was conducted among 250 hypertensive patients who were randomly sampled at the Primary Care Centre of the Universiti Kebangsaan Malaysia Medical Centre (PCC UKMMC) from October 2011 to January 2012. All respondents completed a self-administered questionnaire comprising three sections: (1) Socio-demographic data, (2) Illness perception score, measured using the Malay version of Brief Illness Perception Questionnaire (BIPQ) and (3) Malay version of depression and anxiety, assessed by the Hospital Anxiety and Depression Scale (HADS). Data entry and analysis were done using Statistical Package for Social Sciences (SPSS) version 19.0. Results: The total illness perception score was signfiicantly higher among Malay 5.13 (95% CI: 2.21, 8.05), those with positive family history 5.43 (95% CI: 2.14, 8.72) and respondents who have anxiety 8.56 (95% CI: 4.39, 12.73). Conclusion: Primary care providers need to identify these three significant factors that are associated with patients' illness perception when managing hypertensive patients. Steps need to be taken to screen and treat anxiety among this group of patients. [ABSTRACT FROM AUTHOR]