Abstract: An improved biopsy needle is disclosed in a negative pressure biopsy needle comprising a cannula axially mounted to an elongated chamber with an inner solid stylet initially positioned with a cutting tip externally of the cutting edge of the cannula and extending axially through the elongated chamber exteriorly to an enlarged plunger with an annular plug mounted on an intermediate section of the stylet within the elongated chamber, whereby on relative movement of the elongated chamber and cannula away from the plunger, negative pressure will be effective within the cannula as it penetrates into tissue to core a biopsy. A spring biased mounting device is also provided to initially hold the cannula, elongated chamber and inner stylet and to move the elongated chamber and cannula relative to the inner stylet on firing a holding means.