In a twin clutch type speed change control system in which changeover of gear position is carried out by switching between a pair of clutches, to suppress the noises of clutch being in the disengaged condition during a normal operation with a fixed gear position. In the twin clutch type speed change control system, changeover of gear position between an odd-ordinal gear position and an even-ordinal gear position is effected by disengaging an engaged clutch and engaging a disengaged clutch. During the normal operation with a fixed gear position, the clutch being in the disengaged condition is supplied with a minute oil pressure toward the clutch engaging side, whereby the clutch is moved by a minute amount toward the clutch engaging side.