To provide an interline rod having a simple structure and adjustable of the whole length of the fishing rod on use.

The interline rod is equipped with a tapered cylindrical base rod 1 having a reel seat 5 on the peripheral surface and a base upper rod 2 connected to the tip top-side of the base rod 1 by a shaking-out form. The base upper rod 2 has the following: the first engaging part 2a which is formed on the outer peripheral surface of the end part on the base rod-side and can engage with the inner peripheral surface of the end part on the tip top-side of a base rod 1; and a thick-walled part 7 which has a larger diameter and thicker wall than the part approaching the peripheral surface on the tip top-side of the base rod 1 and has a fishing line introducing opening 8 on it. The thick- walled part 7 constitutes the second engaging part capable of engaging with the inner peripheral surface on the tip top-side of the base rod 1.