OBJECTIVES: With an increase and diversity in ethnic populations in Westernized countries, understanding the differences in levels of knowledge surrounding hypertension is important in planning appropriate prevention strategies. The purpose of our study was to assess levels of hypertension knowledge in Chinese, Indian and White populations in a large metropolitan Canadian city. DESIGN: A telephone survey was conducted in English, Chinese (Cantonese and Mandarin) and Indian languages (Hindi, Punjabi and Urdu). Hypertension knowledge was assessed through a 10-item validated instrument; respondents received 1 point for each correct answer. Logistic regression was used to test differences in hypertension knowledge among these three populations. RESULTS: Survey response rates were 68.7% (301) for Chinese, 61.3% (248) for Indian and 69.7% (254) for White populations. The average hypertension knowledge score for Chinese respondents was 7.23 out of 10, 7.11 for Indian respondents and 7.28 for White respondents. Compared to White respondents, Chinese respondents were less likely than White respondents to know high blood pressure can cause heart attacks (adjusted odds ratio [aOR]: .43, 95% confidence interval [CI]: .19-.96] and Indian respondents were less likely to know losing weight usually decreases blood pressure (aOR: .38, 95% CI: .21-.68). CONCLUSIONS: Hypertension knowledge levels among these three ethnic/racial populations were similar and relatively high and varied by content. Low levels of knowledge for Chinese and Indian ethnic populations were on hypertension risk factors, long-term consequences of hypertension and anti-hypertensive medication adherence. Specifically, females, recent immigrants to Canada and Chinese seniors were identified as sub-groups who should be targeted for hypertension knowledge promotion.