During routine dissection which was carried out for medical students, in a female cadaver which was aged about 40 years, a circumaortic left renal vein draining into inferior vena cava was observed. The left renal vein was duplicated, one being preaortic (anterosuperior) and other being postaortic (posteroinferior). The anterior vein ran at right angles to open into inferior vena cava (as has been shown in [ DisCussionThe left and right renal veins are of large sizes and they run in front of renal arteries and renal pelvis. They open into the inferior vena cava, almost at right angles. The left renal vein is thrice as long as the right one and it crosses the posterior abdominal wall by passing in front of aorta, at the level of transpyloric plane. Its two important tributaries are left supra renal and left gonadal (testicular or ovarian) veins. Occasionally, it may be duplicated, as in this case, where one passes in front and the other behind the aorta, as a result of persistent pre and postaortic anasomotic (ventral and dorsal limbs) channels [1].It is derived from the renal collar (circumaortic renal venous ring) at an embryonic stage and is completed by the persistence of both ventral (preaortic) limb and dorsal (postaortic) limb at a later stage [1]. Left renal vein is a composite vessel which develops from three sources, they are [1]. Cranial portion of sub cardinal vein, [2]. Anastomosis between left sub cardinal and supra cardinal veins and [3]. preaortic anastomosis between the right and left sub cardinal veins. As the anastomosis between two sub cardinal and supra cardinal veins regresses, ventral and dorsal anastomotic channels are formed. During the normal formation of left renal vein, the dorsal vessel degenerates and the ventral vessel becomes the renal vein. Occasionally, it may be duplicated, as in this case, where one passes in front and the other behind the aorta, as a result of persistent pre and postaortic anasomotic (ventral and dorsal limbs) channels. Thus, the dorsal aorta is encircled by a renal collar, wherein preaortic anastomosis persists, as the left renal vein and the postaortic anastomosis form the retroaortic left renal vein [2]. Drainage of lumbar vein may also be anomalous in these cases, as in this, where it opens into retroaortic renal vein. Computerized tomography and computerized tomographic venography are tools essential for identifying vascular anomalies such as circumaortic and retroaortic left renal veins [3]. Identification of this anomaly is very important in preoperative planning for nephrectomy, partial nephrectomy, and living donor nephrectomy. Circumaortic left renal vein is an uncommon anomaly which can be associated with intermittent haematuria [4]. Angiogram reveals double left renal veins in the form of a venous collar. Computed tomography depicts the preaortic and retroaortic left renal veins clearly [3,5]. In a survey of haematuria, circumaortic renal vein should be taken into consideration in a differential diagnosis, and an appreciation of the specific radio...