A corrugated tube of the present invention has a rigid portion, a bellows portion, and a gradually varying portion. The rigid portion is formed in an end portion of the tube, and has a first half-circumference portion having a recess/projection-repetitive structure in which grooves and projection strips are arranged alternately in the tube longitudinal direction and a second half-circumference portion having a straight structure with no grooves or projection strips. The bellows portion is formed in a center portion of the tube and has the first and the second half-circumference portions both of which have a recess/projection-repetitive structure. The gradually varying portion is formed between the rigid portion and the bellows portion, and has the first half-circumference portion having the recess/projection-repetitive structure and the second half-circumference portion having the gradually varying structure in which the height of the projection strip decreases gradually from the bellows portion to the rigid portion.