The results of epidemiological studies of venous thromboembolic disease (VTD) vary widely, depending both on the geographical area and study type. In Spain, there are no data on the incidence and distribution of VTD. To determine the incidence and distribution of this disease, we analyzed the hospital discharges codified by the Spanish national health system. The results of the analysis showed that VTD represented 0.82% (0.69%-0.92%) of all hospital discharges in Spain between 1999 and 2005. The rate of diagnoses for all hospital discharges in 2005 was 103/100,000 inhabitants, with an estimated number of total diagnoses in Spain (hospitalized or not) of 154/100,000. Fifty-three percent were pulmonary embolisms (PE), which showed a tendency to increase, and 47% were deep venous thrombosis (DVT), which showed a tendency to decrease. The mean age was 65 years in men (51% of cases) and 68 years in women, with the incidence increasing exponentially with age. The mean age in patients with PE was 70 years vs 64 years in DVT. Mortality associated with PE was 11.6% vs 2.3% with DVT. DVT occurred during admission in 4% (3-4.7) of persons hospitalized for any cause, 74% of patients being admitted for medical problems. These data reveal that DVT is a serious health problem in Spain, with high morbidity and mortality. The incidence of this disease seems to be increasing and is particularly associated with medical problems, despite improved diagnosis and the accumulated evidence on thromboprophylaxis. Therefore, greater efforts should be made both to improve identification of at-risk patients and the application of prevention protocols.