An improved biopsy needle suitable for obtaining a core sample from a prostate gland. A handle which may be held in the palm of the physician's hand is provided with a forward extending guide tube. A cannula with a sharpened distal end is slidably disposed within the guide tube and is movable by a thumb tab from a retracted position within the guide tube to an extended position in which the cutting edge extends from the guide tube. A sampling stylet having a sharpened distal end and a sample-collecting slot therein is telescopically disposed within the cannula and projects from the rear of the handle. A knob at the proximal end of the stylet permits movement from a retracted position in which the pointed tip of the stylet projects slightly from the distal end of the guide tube to an extended position in which the pointed distal end extends from the guide tube distal end. The physician holding the handle in the palm of his hand places his index finger at the distal end of the guide tube and guides the distal end to a selected point on the prostate gland transrectally. Upon locating the desired point, the hand holds the instrument steady while the other hand pushes the stylet forward into the tissue, pushes the cannula forward to sever tissue within the sampling slot, and the device is then withdrawn with the desired sample.