To study the association of serotonin transporter gene polymorphisms and osteoporosis.Blood samples were collected from 186 individuals with normal bone mineral density and 89 with osteoporosis. Serotonin transporter gene polymorphisms 5HTTVNTR and 5HTTLPR were studied by PCR and statistical analyses used to test the association between groups.The frequency of 12/10 and 12/12 genotypes of 5HTTVNTR was significantly higher among the osteoporotic patients (OR=2,620 CI 95% [1,112--6,172], P=0,037). For 5HTTLPR we did not find significant differences between the two studied groups.As far as we know, this is one of the few studies that report an association between 5HTTVNTR and osteoporosis opening the hypothesis that the determination of this specific serotonin transporter gene polymorphism may contribute to the identification of individuals at high risk for the development of osteoporosis.