A printing device for printing and forming dots on a printing medium comprising: a printing unit that prints an image; wherein the printing of the image is performed such that when the dots are formed on the printing medium in accordance with dot data indicating existence or non-existence of a dot formation per each pixel, the dot formation is divided into at least first and second pixel groups, and at least a portion of dot formation in the first and second pixel groups is performed in a common region; wherein the printing unit includes a print head for performing a color printing by multiple color dots in a resolution N, N is a natural number of more than 180, dots per inch (dpi), and when the printing is performed in each of a plurality of conditions in which a difference of a dot pitch between a formation position of one dot belonging to the first pixel group and a formation position of dot, which corresponds to the one dot and should be adjacent to the one dot, belonging to the second pixel group, is 2/720 inch to 5/720 inch, at least one of following conditions A, B, C is satisfied: A: when the printed image is yellow, RGB value: R = G = 255, B = 0 to 64, when RGB value is 8 bit conversion, color difference in CIEL*a*b* color space of images printed in each of the plurality of different conditions is less than value 2 as a change of b*; B: when the printed image is magenta, RGB value: R = B = 255, G = 0 to 64, when RGB value is 8 bit conversion, the color difference in CIEL*a*b* color space of the images printed in each of the plurality of different conditions is less than value 0.5 as a change of L* or less than value 0.5 as a change of a*; and C: when the printed image is cyan, RGB value: G = B = 255, R = 0 to 64, when RGB value is 8 bit conversion, the color difference in CIEL*a*b* color space of the images printed in each of the plurality of different conditions is less than value 0.5 as a change of L*. a printing unit that prints an image; wherein the printing of the image is performed such that when the dots are formed on the printing medium in accordance with dot data indicating existence or non-existence of a dot formation per each pixel, the dot formation is divided into at least first and second pixel groups, and at least a portion of dot formation in the first and second pixel groups is performed in a common region; wherein the printing unit includes a print head for performing a color printing by multiple color dots in a resolution N, N is a natural number of more than 180, dots per inch (dpi), and when the printing is performed in each of a plurality of conditions in which a difference of a dot pitch between a formation position of one dot belonging to the first pixel group and a formation position of dot, which corresponds to the one dot and should be adjacent to the one dot, belonging to the second pixel group, is 2/720 inch to 5/720 inch, at least one of following conditions A, B, C is satisfied: A: when the printed image is yellow, RGB value: R = G = 255, B = 0 to 64, when RGB value is 8 bit conversion, color difference in CIEL*a*b* color space of images printed in each of the plurality of different conditions is less than value 2 as a change of b*; B: when the printed image is magenta, RGB value: R = B = 255, G = 0 to 64, when RGB value is 8 bit conversion, the color difference in CIEL*a*b* color space of the images printed in each of the plurality of different conditions is less than value 0.5 as a change of L* or less than value 0.5 as a change of a*; and C: when the printed image is cyan, RGB value: G = B = 255, R = 0 to 64, when RGB value is 8 bit conversion, the color difference in CIEL*a*b* color space of the images printed in each of the plurality of different conditions is less than value 0.5 as a change of L*. A: when the printed image is yellow, RGB value: R = G = 255, B = 0 to 64, when RGB value is 8 bit conversion, color difference in CIEL*a*b* color space of images printed in each of the plurality of different conditions is less than value 2 as a change of b*; B: when the printed image is magenta, RGB value: R = B = 255, G = 0 to 64, when RGB value is 8 bit conversion, the color difference in CIEL*a*b* color space of the images printed in each of the plurality of different conditions is less than value 0.5 as a change of L* or less than value 0.5 as a change of a*; and C: when the printed image is cyan, RGB value: G = B = 255, R = 0 to 64, when RGB value is 8 bit conversion, the color difference in CIEL*a*b* color space of the images printed in each of the plurality of different conditions is less than value 0.5 as a change of L*.