An ECU executes a program that includes the steps of setting a line pressure to a line pressure (1) that is appropriate for improving fuel efficiency, if an automatic transmission is not shifting, and a deceleration slip control for a lock-up clutch is not being executed; setting the line pressure to a line pressure (2) that is equal to or lower than a line pressure (3) that is appropriate when the automatic transmission is shifting, if it is determined that the automatic transmission is not shifting, and the deceleration slip control is being executed; and setting the line pressure to the line pressure (3), if it is determined that the automatic transmission is shifting. The line pressure (1) is lower than the line pressure (2). The line pressure (2) is equal to or lower than the line pressure (3).