This device is adapted for taking venous blood samples without the aid of any auxiliary negative pressure. Venous blood pressure is the sole force which fills the device with the blood sample. The device includes a flexible plastic tube formed from polyethylene or the like and further includes a blood drawing needle mounted on one end of the tube. The tube is divided into a collection reservoir into which the sample is drawn, and a sampling reservoir into which the sample may be expressed from the collection area. A valve separates the two areas. Also included in an elastomeric needle closure which adapts the device for in situ centrifugation of the blood sample in a test tube.