A varnishing apparatus comprising: a varnishing unit including a first varnishing unit configured to apply varnish to one surface of a sheet; and an additional processing unit provided on an upstream side in the sheet conveyance direction with respect to the varnishing unit and configured to perform additional processing on the sheet, wherein the additional processing unit includes a first embossing unit configured to perform embossing on the sheet, and a special unit provided on the upstream side in the sheet conveyance direction with respect to the first embossing unit and configured to perform additional processing on the sheet, characterized in that the varnishing apparatus is a double-sided varnishing apparatus, wherein the varnishing unit further includes a second varnishing unit arranged on a downstream side in a sheet conveyance direction with respect to the first varnishing unit and configured to apply varnish to the other surface of the sheet, the special unit includes a main body including a frame, a first impression cylinder rotatably supported by the frame and configured to convey the sheet, and a processing cylinder rotatably supported by the frame and facing the first impression cylinder, the double-sided varnishing apparatus further comprises: an offset printing module including a plate cylinder and an inking device and configured to be attachable to the main body and detachable from the main body, a flexographic printing module including an anilox roller and a chamber device and configured to be attachable to the main body and detachable from the main body, the processing cylinder configured by a blanket cylinder and the offset printing module attached to the main body constitute an offset printing unit which performs offset printing on the sheet, the processing cylinder configured by a flexographic plate cylinder and the flexographic printing module attached to the main body constitute a flexographic printing unit which performs flexographic printing on the sheet, and the processing cylinder configured by an embossing cylinder constitutes a second embossing unit which performs embossing on the sheet. a varnishing unit including a first varnishing unit configured to apply varnish to one surface of a sheet; and an additional processing unit provided on an upstream side in the sheet conveyance direction with respect to the varnishing unit and configured to perform additional processing on the sheet, wherein the additional processing unit includes a first embossing unit configured to perform embossing on the sheet, and a special unit provided on the upstream side in the sheet conveyance direction with respect to the first embossing unit and configured to perform additional processing on the sheet, characterized in that the varnishing apparatus is a double-sided varnishing apparatus, wherein the varnishing unit further includes a second varnishing unit arranged on a downstream side in a sheet conveyance direction with respect to the first varnishing unit and configured to apply varnish to the other surface of the sheet, the special unit includes a main body including a frame, a first impression cylinder rotatably supported by the frame and configured to convey the sheet, and a processing cylinder rotatably supported by the frame and facing the first impression cylinder, the double-sided varnishing apparatus further comprises: an offset printing module including a plate cylinder and an inking device and configured to be attachable to the main body and detachable from the main body, a flexographic printing module including an anilox roller and a chamber device and configured to be attachable to the main body and detachable from the main body, the processing cylinder configured by a blanket cylinder and the offset printing module attached to the main body constitute an offset printing unit which performs offset printing on the sheet, the processing cylinder configured by a flexographic plate cylinder and the flexographic printing module attached to the main body constitute a flexographic printing unit which performs flexographic printing on the sheet, and the processing cylinder configured by an embossing cylinder constitutes a second embossing unit which performs embossing on the sheet. an offset printing module including a plate cylinder and an inking device and configured to be attachable to the main body and detachable from the main body, a flexographic printing module including an anilox roller and a chamber device and configured to be attachable to the main body and detachable from the main body, the processing cylinder configured by a blanket cylinder and the offset printing module attached to the main body constitute an offset printing unit which performs offset printing on the sheet, the processing cylinder configured by a flexographic plate cylinder and the flexographic printing module attached to the main body constitute a flexographic printing unit which performs flexographic printing on the sheet, and the processing cylinder configured by an embossing cylinder constitutes a second embossing unit which performs embossing on the sheet.