A hydraulic control apparatus may be provided with a lock-up clutch operated or not by hydraulic pressure difference between an engagement-side oil chamber and a disengagement-side oil chamber and may include a first hydraulic line supplying hydraulic pressure to the disengagement-side oil chamber or exhausting the hydraulic pressure from the disengagement-side oil chamber, a second hydraulic line supplying hydraulic pressure to the engagement-side oil chamber or exhausting the hydraulic pressure from the engagement-side oil chamber, and a third hydraulic line connected to a slip switch valve, and selectively exhausting through the slip switch valve the hydraulic pressure supplied to the engagement-side oil chamber.