Objective: To evaluate ethnic and anthropometric correlates of adiposity among a nationally representative, multi-ethnic, Trinidadian pre-school population. Design: Cross-sectional study conducted between June 2008 and July 2009. Setting: Government and privately owned Early Childhood Care and Education Centres in Trinidad. Subjects: A total of 596 pre-school children (aged 31-73 months) from thirty-four schools had their weight, height, mid-upper arm circumference, waist circumference, biceps and triceps skinfold thicknesses measured by a registered dietitian using standard procedures. Percentage body fat was estimated using a foot-to-foot bioelectric impedance analyser (Tanita 531, Tokyo, Japan). Date of birth, religion and ethnicity were extracted from school records and pre-schoolers' ethnicity was categorized as East Indian, African, Mixed (a combination of two or more ethnicities), Chinese or Caucasian. Results: Anthropometric variables explained significantly more of the variance in adiposity among girls (67?4-88?1 %) than boys (24?4-39?2 %; P , 0?0 0 1). Pre-schoolers of African descent were significantly taller, heavier and had higher abdominal fat and mid-upper arm circumference than their East Indian and Mixed counterparts (all P , 0?001). The overall prevalence of excess adiposity ($25 % body fat) as determined by bioelectrical impedance was 14?6 %, while 2?9 % of the children were undernourished according to WHO weight-for-age criteria. Differences in anthropometry were non-existent between children attending government and private pre-schools. Conclusions: Gender, ethnicity and anthropometry all explained excess adiposity in these pre-schoolers. These findings highlight the need to elucidate the mechanisms that may be involved in explaining these differences, particularly those of ethnic origin.