An endoscope 10 includes a lens 31, a lens frame 34 that holds the lens 31, and a bonding member 33 that water-tightly fixes the lens 31 to the lens frame 34, the bonding member composed of Sn-alloy solder containing at least one of Zn, Sb, A1 and In, having a melting point not higher than 200°C and forming a chemical bond via oxygen, and the lens, the lens frame and the bonding member are provided at a distal end portion 11A of an insertion portion 11.