A printer having a first printing mode in which information is printed in a normal image on a general printing tape and a second printing mode in which information is printed in a mirror image on a transfer tape. When the printer prints a two-dimensional code symbol image 40b in the second printing mode on the transfer tape 31b, the printer also prints a two-dimensional code symbol image 40a in the normal image in an area of the transfer tape next to its area in which the symbol image is printed in the mirror image. At this time, an additional confirmative indication 42 is printed close to the symbol image 40a printed in the normal image to indicate that this symbol image should be used only for confirming the content of the symbol image printed in the mirror image.