One solenoid valve included in a hydraulic pressure control device has at least two functions among the following (1) to (6) functions, (1) switching a state of a two-way clutch, (2) switching a state of a parking lock mechanism, (3) switching the supply of hydraulic pressure to a first brake that is put into an engaged state when a gear stage selected when driving of a vehicle starts is set, (4) controlling a line pressure adjustment valve so that a decrease in a line pressure is prevented when the temperature of a hydraulic fluid is a first predetermined temperature or higher, (5) preventing the occurrence of a creep phenomenon in a neutral range when the temperature of the hydraulic fluid is a second predetermined temperature or lower, and (6) boosting a line pressure by performing switching to another linear solenoid valve when the line pressure adjustment valve has failed.