Retinal microvascular caliber is a risk marker for cardiovascular disease. The authors examined the relation between high-sensitivity C-reactive protein (hsCRP) and retinal microvascular caliber in a multiethnic Asian population (n = 3,583) of Chinese, Malays, and Indians aged 24-95 years residing in Singapore (2003-2007). Retinal arteriolar and venular diameters were measured and summarized as central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE), respectively. Persons with higher levels of hsCRP had wider CRVE (P(trend) < 0.001). In subgroup analysis stratified for different cardiovascular disease risk factors, the association between hsCRP and CRVE was seen in persons without diabetes (P(trend) < 0.001) but was absent in persons with diabetes (P(trend) = 0.200; P(interaction) = 0.004). No significant interaction between race/ethnicity and hsCRP in relation to retinal vascular caliber was observed. These data suggest that retinal venular caliber is associated with higher levels of hsCRP in Asians, which is consistent with studies in white Caucasian populations, further supporting the concept that retinal venular caliber may be a marker for low-grade systemic inflammation.