Background: Ethnic factors are involved in the risk, for osteoporosis and hip fracture. Aim: To assess the effect of Mapuche ethnicity on the risk for hip fracture. Patients and methods: A case control study. Cases were subjects over 55 years of age: admitted, during one year,for hip fracture not associated to major trauma or tumors. Controls were randomly chosen front other hospital services and paired,for age with cases. The magnitude of the association between ethnicity and hip fracture was expressed as odds ratio in a logistic regression model. Results: In the study period, 156 cases with hip fracture were admitted. The proportion of subjects with Mapuche origin was significantly lower among cases than controls (11.8 and 26.5% respectively, p < 0.001). In the logistic regression model, Mapuche ethnicity was associated with hip fracture with an odds radio of 0,14 (p = 0.03, 95% CI 0.03-0.8). Conclusions: In this sample, Mapuche ethnicity is a protective factor for hip fracture.