The etiologies of the portal vein trombosis are dominated by the neoplasic forms with hepatocellular carcinoma; we report a rare case of portal and splenic veins thrombosis revealing a liver military tuberculosis occuring in a HIV 1 infected patient. A 42 years old senegalese woman with no personal or family history of thrombosis was admitted for abdominal upper right quadran, and epigastric pain, with fever and important weight loss. Ultrasound identified endoluminal echogenic images in the portal and splenic veins. There were no lymph nodes or liver tumor. Evaluations of proteins C and S were normal and there was no anticardiolipin antibody. In searching the aetiology of the thrombosis, a liver biopsy was performed, and showed a miliary tuberculosis. an HIV 1 infection was later on diagnosed. The antituberculosis treatment associated with heparine therapy was successful, the thrombosis resolved entirely. This portal and splenic veins thromboses occuring on a miliary tuberculosis of the liver seems to be an exceptional situation. We did not found in the literature a similar case.lt points out the interset of liver biopsy in searching the aetiology and the early heparine therapy set up