[Problem] An object of the present invention is to provide a catheter and balloon catheter in which an outer layer is not easily detached from an inner layer even when the outer layer is dragged in the axis direction (the distal end and proximal end directions). [Solution] According to the catheter 1, the outer layer 40 has the protrusion part 50 in a location of the depressed portion 24 of the inner layer 10, the protrusion part 50 entering deeper than the reinforcement layer (coil body) 30 through the gap 25 and extending in the axis direction of the catheter 1. This can improve the joining strength between the inner layer 10 and the outer layer 40. Further, the risk of detachment of the outer layer 40 from the inner layer 10 can be reduced by virtue of the anchoring effect in which the protrusion part 50 of the outer layer 40 is caught in the reinforcement layer (coil body) 30 even when the outer layer 40 is dragged in the axis direction (the distal end and proximal end directions) at a stenosis site or an obstructed segment upon insertion of the catheter 1 into a blood vessel, bile duct, pancreatic duct, and the like.
