Priciples of kont-tying have assumed a new and enhanced role in operative laparoscopy. The surgeon should be familiar with extracorporeal knot-tying techniques. For extracorporeal knot-tying, a knot pusher is used to properly secure the knot. But a knot pusher has some limitation for tightening of the knot. I developed an instrument which has a slit and hole.(slit for knot pushing and hole for knot tightening) for a secure knot. By using this instrument(Lee's knot presser) it is very easy and secure for knot-tying. The surgeon can confirm and control the knot tightening.