We reviewed 8 cases of renal vein thrombosis, 4 of which were detected at autopsy, 1 by laparotomy and the remaining 3 by venography. In 4 cases malignancy also was found and in 2 membranous glomerulonephritis was noted. In 1 patient the thrombosis occurred in a solitary kidney, while it was bilateral in 3. The 4 patients in whom the diagnosis was made during life were treated with anticoagulants alone and 3 are alive with stable renal function 3, 4 and 7 1/2 years after diagnosis.