A hydraulic pressure control device including a pump driven to generate hydraulic pressure; a first pressure regulation valve that regulates hydraulic pressure in a first passage coupled to a pump along with discharge of oil; a second pressure regulation valve that receives the hydraulic pressure in the first passage and regulates the hydraulic pressure to an engagement pressure to engage a lock-up clutch according to a first signal pressure to output the engagement pressure to a second passage that supplies the oil to an engagement chamber; and a third pressure regulation valve that receives the hydraulic pressure in the first passage or the engagement pressure output to the second passage and regulates the received pressure according to the first signal pressure or a second signal pressure that synchronizes with the first signal pressure to output the resulting pressure to a third passage that supplies the oil to the disengagement chamber.