Automobile seat which is convenient to adjust the height of a headrest

The invention discloses an automobile seat which is convenient to adjust the height of a headrest. The headrest is provided with a bar body extending downward, which comprises a left bar and a right bar, and the left bar and the right bar are inserted at the upper end of the seat back. The upper end of the seat back is provided with an adjusting device which is cooperatively installed with the rodbody. The adjusting device comprises a mounting base body. A button, a first locking plate and a second locking plate are slidably installed in the mounting base body along the length direction of the seat back. The button has a first unlocking state and a second unlocking state within the travel range of the button. In the first unlocked state, the button pushes the first locking plate to move,and the lever body can move up and down relative to the adjusting device; In the second unlocked state, the button pushes the second locking plate to move and the lever body can be disengaged from theadjusting device. The tech