Abstract: A cannula for preventing spraying of liquid is disclosed. The cannula includes a support tube partially inserted into a human body to guide a surgical instrument to an inside of the human body and a handle integrally formed with the support tube to allow the surgical instrument to be in and out of the human body, wherein the handle further includes a plurality of seal plates coupled to an inside thereof to prevent spraying of liquid onto an operator by an internal pressure of the human body and an outlet formed at a side surface thereof to reduce an internal pressure of the handle to atmospheric pressure.