According to the present disclosure, provided is a surgical instrument in which an actual motion of bending an end tool or performing a surgical treatment intuitively matches a motion of a manipulation portion corresponding thereto. In detail, to this end, provided are an end tool having various degrees of freedom, a manipulation portion having a structure to enable intuitive manipulation of a motion of the end tool, and a driving force transmission portion for transmitting a driving force of the manipulation portion to the end tool so that the end tool operates as manipulated by the manipulation portion.