A control device for a dual-clutch transmission in which a clutch device including a first clutch and a second clutch is provided between a driving source and a transmission mechanism, a driving power transmission path from the driving source to a vehicle drive system is capable of being switched between a first transmission line via the first clutch and a second transmission line via the second clutch, and shift gears usable in the first transmission line are different from shift gears usable in the second transmission line, wherein a first space, which is provided around first clutch plates for engaging and disengaging the first clutch, and a second space, which is provided around second clutch plates for engaging and disengaging the second clutch, are communicated with each other and are configured to allow a hydraulic oil for cooling to be supplied thereto, the control device comprising: gear changing control means configured to, when shifting which involves switching between the first transmission line and the second transmission line and changing of shift gears used in a switching transmission line being switched to is performed, perform changing of the shift gear used in the switching transmission line being switched to, if a clutch of a switching transmission line being switched from is in an engaged state and also a clutch of the switching transmission line being switched to is in a disengaged state; and lubrication control means configured to, in at least one of: (i) a case where, when upshifting which involves switching between the first transmission line and the second transmission line and changing of the shift gear used in the switching transmission line being switched to is performed, a number of revolutions of an input shaft (31, 32) connected to a to-be-engaged clutch, which is the clutch of the switching transmission line being switched to, is higher than a number of revolutions of the driving source before the upshifting is performed; or (ii) a case where, when downshifting which involves the switching between the first transmission line and the second transmission line and the changing of the shift gear used in the switching transmission line being switched to is performed, the number of revolutions of the input shaft (31, 32) connected to the to-be-engaged clutch is lower than the number of revolutions of the driving source before the downshifting is performed, increase an amount of the hydraulic oil, which is to be supplied to the first space and the second space, to a second lubrication amount larger than a predetermined first lubrication amount during at least a part of a period of time from when gear disconnecting of a shift gear before being changed is completed until the number of revolutions of the input shaft (31, 32) becomes equal to the number of revolutions of the driving source. gear changing control means configured to, when shifting which involves switching between the first transmission line and the second transmission line and changing of shift gears used in a switching transmission line being switched to is performed, perform changing of the shift gear used in the switching transmission line being switched to, if a clutch of a switching transmission line being switched from is in an engaged state and also a clutch of the switching transmission line being switched to is in a disengaged state; and lubrication control means configured to, in at least one of: (i) a case where, when upshifting which involves switching between the first transmission line and the second transmission line and changing of the shift gear used in the switching transmission line being switched to is performed, a number of revolutions of an input shaft (31, 32) connected to a to-be-engaged clutch, which is the clutch of the switching transmission line being switched to, is higher than a number of revolutions of the driving source before the upshifting is performed; or (ii) a case where, when downshifting which involves the switching between the first transmission line and the second transmission line and the changing of the shift gear used in the switching transmission line being switched to is performed, the number of revolutions of the input shaft (31, 32) connected to the to-be-engaged clutch is lower than the number of revolutions of the driving source before the downshifting is performed, increase an amount of the hydraulic oil, which is to be supplied to the first space and the second space, to a second lubrication amount larger than a predetermined first lubrication amount during at least a part of a period of time from when gear disconnecting of a shift gear before being changed is completed until the number of revolutions of the input shaft (31, 32) becomes equal to the number of revolutions of the driving source.