The invention describes a device and a method for internal coating of cavities of workpieces by thermal spraying, comprising a burner for spraying a coating material, the burner being received on a positioning device for allowing positioning at least in one direction, and further comprising a rotary plate, which can be driven in rotary fashion and on which is provided a workpiece holder for a workpiece that can be positioned relative to the burner by means of a guiding device. The guiding device comprises at least one first linear guide with a first drive means for positioning the workpiece holder, and at least one second linear guide with a second drive means for positioning a balancing weight. The first and the second drive means are driven in opposite senses, which guarantees continuous balancing of the masses when the workpiece is displaced. In order to ensure continuous evacuation of overspray, the rotary plate is provided, in the area of its axis of rotation, with an opening to which an exhaust system can be connected.