手术刀，在中文也常称柳叶刀，是根据它的形状来称呼的名字。是一种做外科手术时用来切割的一种医疗器械。

一把手术刀由一个刀柄和一个刀刃组成。刀刃可以有多种形式（比如右手侧的，弯曲的，镰刀状的等等）。 它非常锋利，切割起来不必花费力气。手术刀只可以单独使用。一般用塑料包装，也可以用金属包装。这种情况手术刀片只能一次性使用。

A scalpel, or lancet, is a small and extremely sharp bladed instrument used for surgery, anatomical dissection, and various arts and crafts (called a hobby knife). Scalpels may be single-use disposable or re-usable. Re-usable scalpels can have permanently attached blades that can be sharpened or, more commonly, removable single-use blades. Disposable scalpels usually have a plastic handle with an extensible blade (like a utility knife) and are used once, then the entire instrument discarded. Scalpel blades are usually individually packed in sterile pouches but are also offered non-sterile. Double-edged scalpels are referred to as "lancets".