An endoscope device comprising: an elongated tubular insertion part a plurality of arm members which is provided in the distal portion of the insertion part so as to protrude forward and is capable of treatment with a treatment tool inserted thereinto an observation main body provided in the distal portion of the insertion part so as to freely separate from the insertion part an energization member which energizes the observation main body disposed within the distal portion of the insertion part toward the direction opposite to the plurality of the arm members in the radial direction of the insertion part and a holding mechanism which resists the energization member to hold the observation main body in a state where the observation main body is disposed within the distal portion of the insertion part and is capable of releasing the holding state.
