Abstract: A supporting structure (10) moves along panel joints (J), (J) of a roof panel (R) and a roof side panel (S) of an automobile body (B). Two sealant coating devices (20, 30), which each have a coating head, are provided on the left and right sides of the supporting structure (10). The sealant coating devices (20, 30) are mounted on the supporting structure 10 in such a manner that the coating heads can move in the width direction as well as in the vertical direction of the automobile body. According to this arrangement, the sealant coating devices (20, 30) move in such a manner that the coating head follows the panel joints (J), (J) while the supporting structure (10) along the longitudinal direction of the automobile body (B).