There is provided a small-sized and inexpensive rotational adjustment apparatus for a linearly moveable inkjet coating head 6 without providing a rotary mechanism which is separate from and independent of a linear movement mechanism. The apparatus is capable of performing a rotational adjustment, about a rotary axis in a Z-axis direction, of the inkjet coating head in which the Z-axis direction is orthogonal to an X-axis direction which is a direction of movement of the coating head. The apparatus has: first and second moveable bodies, two in total, which are linearly moved by separate driving sources in the X-axis direction; and a converting mechanism which converts the inkjet coating head into a linear movement in the X-axis direction when the first and second moveable bodies synchronously move in the X-axis direction, and into a rotary movement, about the rotary axis of the inkjet coating head, when both the first and the second moveable bodies make a relative movement in the X-axis direction.