Although several epidemiological studies have investigated the relationship between type 2 diabetes mellitus (T2DM) and hip circumference or height, the results are inconsistent. The present systematic review and meta-analysis of published observational studies was conducted to assess the effects of hip circumference and height on diabetes risk. Online databases were searched through January 2012, and the reference lists of pertinent articles reporting observational studies in humans were examined. Pooled relative risks (RR) and 95% confidence intervals (CI) were calculated with a random-effects model. Eighteen studies (nine cross-sectional and nine cohort) were included, with 250,497 participants and 7,765 cases of T2DM. Hip circumference was inversely associated with an increased risk of T2DM in men (summary RR [95% CI] 0.60 [0.45, 0.80]) and women (0.54 [0.42, 0.70]). These results were consistent between cross-sectional and cohort studies. An inverse association between height and T2DM was observed in women only (summary RR [95% CI] 0.83 [0.73, 0.95]). Our meta-analysis strongly supports an inverse relationship between hip circumference and risk of T2DM in men and women. The inverse association between height and risk was significant only in women.