To provide an insertion tube for injecting a body fluid leakage-preventing agent for a dead body simply insertable into body cavities such as a mouth, nostrils and ears of the dead body and having excellent operation efficiency without requiring skill and without causing problems that a tip opening of the insertion tube is closed to hardly inject the body fluid leakage-preventing agent in the course of insertion or the tip is caught with body walls to hardly insert the tube when the insertion tube is inserted into the body cavities of the dead body.

The insertion tube 40 is made of a synthetic resin, has a rear end connected to a discharging cylindrical part 22 at the tip of an injector 10 for the body fluid leakage-preventing agent and is used by insertion into the body cavities of the dead body for injecting the body fluid leakage-preventing agent X in the injector into the body cavities. A closing member 50 having the tip external shape in a nearly hemispherical shape is freely detachably mounted on the tip opening 42 thereof so that the body fluid leakage-preventing agent is simultaneously extruded into the body cavities when the body fluid leakage-preventing agent is injected into the body cavities of the dead body.