A flexible tube for an endoscope forming the insertion part of the endoscope inserted into a body cavity and an endoscope device. The flexible tube comprises a curved part disposed at the tip side thereof and formed to perform curving operation according to the operation of an operator and a flexible tube part having a tip and a base and so formed that the tip is continuously connected to the base end of the curved part. The curved part is characterized by comprising an area where it is curved at a first radius of curvature when the curved part is maximally curved and an area formed at the tip of the flexible tube and set so as to curve at a second radius of curvature smaller than the first radius of curvature when the curved part is passively curved under a prescribed power. Thus, a resistance caused when the curved part passes the bent part of the body cavity can be suppressed, the insertion capability of the insertion part can be increased, and load and pain on patients can be reduced.