An insertion instrument comprises: an elongated insertion section to be inserted into a subject an operation section interconnected with the base end side of the insertion section in the insertion direction thereof and a bendable section including a first bendable portion and a second bendable portion, the first and second bendable portions being bent and operated by an input given by the operation of a bending operation device provided to the operation section. The insertion instrument further comprises: at least two bending wires which are inserted through the insertion section and through the inside of the operation section, bend and operate the bendable section using an input given by the operation of the bending operation device, are inserted through the inside of the insertion section, and are capable of moving forward and backward along the insertion section a wire movement restriction section which restricts the range of forward and backward movement of the bending wires a bending state switching mechanism for switching between the bending states of the bendable section, the switching mechanism being provided to the operation section and switching, using an input given by the operation of the bending operation device, between a first bending state in which the first bendable portion and second bendable portion of the bendable section are bent and operated, and a second bending state in which only the first bendable portion of the bendable section is bent and operated and a switching mechanism for the wire movement restriction section, the switching mechanism switching the wire movement restriction section in synchronism with the operation of switching to the first bending state or the second bending state performed by the bending state switching mechanism.La présente invention concerne un instrument dinsertion comportant : une section dinsertion allongée devant être insérée dans un sujet une section de fonctionnement interconnectée avec le côté dextrémité d
