A protector guard housing is disclosed for a catheter type needle apparatus to prevent accidental needle puncture. The guard housing is initially positioned between the hub of the catheter and the handle of the needle which slidably extends through the catheter in a known manner. A detent mechanism initially retains the forward end of the guard to the catheter hub while needle supports within the guard permits the needle to axially move relative to the guard. When the needle is withdrawn from the catheter after site puncture, a resilient closure wall formed in the protector closes the protector's forward end while the needle's cutting end is simultaneously wedged into contact with friction retention material in the protector. The needle's cutting end is thus encapsulated within the protector when the detent mechanism releases the protector from the catheter.