To provide a method of confirming setting of a paint gun, with which whether the color and setting position of a paint gun for drawing a color line on a tread surface are correct or not can be automatically confirmed, in the tread extrusion line of a tire manufacturing stage.

Reference data related to the color and setting position of a paint gun preliminarily stored in a storage device are displayed. In accordance with the displayed reference data, after the paint gun on which an ID tag with the color data written therein is mounted is set, the color data are read out of the ID tag using an ID reader. Then, the setting position data are prepared by an encoder, the read color data and the prepared setting position data are compared with the reference data by a controller. The comparison result is output from the controller, and whether the setting of the paint gun is correct or not is confirmed from the output comparison result.