In an endoscope system including a plurality of endoscopes 2 including insertion portions 10 having different diameters, each of the plurality of endoscopes 2 includes a first bending portion 7 subjected to bending operation to actively bend, a second bending portion 8 passively bent by external force, a flexible tube portion 9 having rigidity higher than rigidity of the second bending portion 8, and a bending portion 30 including the first bending portion 7 and the second bending portion 8. In the plurality of endoscopes 2, a relation among lengths of the second bending portions 8 is set to be contrary to a size relation among insertion portion 10 diameters.
