In an endoscope therapeutic device having a plurality of introduction guide tubes for introducing a treatment tool into a body cavity, the introduction guide tubes are mutually joined at a position more proximal than bending portions thereof. Accordingly, the effects caused by the movement of the plurality of the introduction guide tubes are mutually invalidated at a joint portion as a fulcrum, so that the position of the introduction guide tube is relatively stabilized in the body cavity. As joining methods, there are integration, usage of a joint tool, and usage of an over tube. The operability is improved when the introduction guide tube is provided at the distal end thereof with a mechanism for retaining and/or rotating a distal end of a treatment tool inserted therethrough.