The invention is to offer a surgical instrument, where the pressure-opposing force and bending characteristics of the spring parts can be easily adjusted and the manipulability is improved. This surgical instrument comprises functional parts 11 that perform nipping or cutting of the object, operating parts 13 that operate the functional parts 11 by a user adding force, and spring parts 14 composed of a pair of elastic strip-shaped parts that impel the operating part 13 in the direction of opening the functional parts 11, wherein multiple grooves 14A are formed in the strip-shaped members of the spring parts 14, thereby to cause changes in pressure-opposing force and in bending characteristics of the spring parts 14, and allowing adjustment of manipulability of the functional parts 11.
