A running gear of a saddle-riding-type vehicle includes a running gear unit with an engine which is pivotally supported to a vehicle body to freely swing, an exhaust pipe extending towards a rear portion of the engine and a support unit for making the running gear unit support a midway section of the exhaust pipe in a longitudinal direction. The support unit includes a first bracket provided on the running gear unit, a second bracket provided on the midway section of the exhaust pipe and a pair of engaging members vertically arranged for engaging a rear end part of the first bracket and a front end part of the second bracket with each other in any relative position in a fore-and-aft direction.