The authors report two cases of primary popliteal venous aneurysm. Thi
s condition is rare. The lesion may be clinically asymptomatic and may
remain unrecognised since it is discovered most often during the inve
stigation of thrombo-embolic complications. The diagnosis is based upo
n ultrasonography and phlebography. Asymptomatic forms should merely b
e monitored. Apart from anticoagulants, the treatment of symptomatic f
orms is surgical. Methods remain controversial.