DVT is a serious condition that remains common despite advances in prophylaxis. It is a condition that poses a serious health problem due to its morbidity and mortality. The aim of our work was to analyse the epidemiological, clinical and biological characteristics of venous thrombosis at the Avicenne Marrakech military hospital. This is a retrospective descriptive study, which focuses on patients with venous thromboembolic disease over a period of 6 years, extending between June 2013 and June 2019, collecting 64 observations. The average age was 50.5 years (extremes: 15-90 years) with a dominant age range (25%) between 40 and 49 years. We note a male predominance with a male/female sex ratio of 1.28. 88% of patients had at least one thromboembolic risk factor. DVT of the lower limbs was the most frequent location (57.8%), with a predominant involvement of the left lower limb in 16 cases (43.2%), The aetiological work-up showed a predominance of acquired thrombophilia, with a high frequency of neoplasia, cancer, and frequency of neoplasia, Behçet's disease and lupus + SAPL. The assessment of of constitutional thrombophilia showed a combined deficiency of protein S and protein C in 1 case, elevation of factor VIII in 2 cases and hyperhomocysteinemia in 1 case. VTE remains a serious condition and is often under-diagnosed, especially in atypical atypical locations. Once the diagnosis has been made, an etiological assessment must be systematic to look for neoplasia in particular. It is only through preventive measures, early diagnosis early diagnosis and effective treatment will reduce the risks.