An inkjet printing device (22,250) comprising: a transport path (Ls) that transports a sheet as a box-making material to be assembled into a polyhedral corrugated box including a plurality of wall portions, in a transport direction; and a plurality of Inkjet heads (23A,23B) that are disposed to face a surface of the sheet in the transport path (Ls) and that are disposed apart from one another in an intersecting direction intersecting the transport direction along the surface of the sheet, wherein the transport path (Ls) transfers the sheet In the transport direction in such a posture that four regions (32A,32B,32C,32D) that are planned to form four side wall portions when the sheet is assembled into the corrugated box are aligned in the intersecting direction, the plurality of Inkjet heads includes a first inkjet head that is capable of printing a predetermined print pattern in a printing range extending over two adjacent regions (P1A) in the intersecting direction among the four regions in the intersecting direction and a second Inkjet head that is capable of printing a predetermined print pattern in a printing range extending over two different regions (P1B) in the intersecting direction, the two different regions (P1B) being different from the two adjacent regions (P1A) adjacent in the intersecting direction, the two adjacent regions (P1A) Include a first region that is planned to form a first wall serving as a length face among the four side wall portions when the sheet is assembled into the corrugated board box, and a second region that is adjacent to the first region in the Intersecting direction and that is planned to form a second wall serving as a width face among the four side wall portions when the sheet is assembled into the corrugated board box, and the two different regions (P1B) include another first region that is planned to form another first wall serving as a length face among the four side wall portions when the sheet is assembled into the corrugated board box, and another second region that is adjacent to the another first region in the intersecting direction and that is planned to form another second wall serving as a width face among the four side wall portions when the sheet is assembled into the corrugated board box. a transport path (Ls) that transports a sheet as a box-making material to be assembled into a polyhedral corrugated box including a plurality of wall portions, in a transport direction; and a plurality of Inkjet heads (23A,23B) that are disposed to face a surface of the sheet in the transport path (Ls) and that are disposed apart from one another in an intersecting direction intersecting the transport direction along the surface of the sheet, wherein the transport path (Ls) transfers the sheet In the transport direction in such a posture that four regions (32A,32B,32C,32D) that are planned to form four side wall portions when the sheet is assembled into the corrugated box are aligned in the intersecting direction, the plurality of Inkjet heads includes a first inkjet head that is capable of printing a predetermined print pattern in a printing range extending over two adjacent regions (P1A) in the intersecting direction among the four regions in the intersecting direction and a second Inkjet head that is capable of printing a predetermined print pattern in a printing range extending over two different regions (P1B) in the intersecting direction, the two different regions (P1B) being different from the two adjacent regions (P1A) adjacent in the intersecting direction, the two adjacent regions (P1A) Include a first region that is planned to form a first wall serving as a length face among the four side wall portions when the sheet is assembled into the corrugated board box, and a second region that is adjacent to the first region in the Intersecting direction and that is planned to form a second wall serving as a width face among the four side wall portions when the sheet is assembled into the corrugated board box, and the two different regions (P1B) include another first region that is planned to form another first wall serving as a length face among the four side wall portions when the sheet is assembled into the corrugated board box, and another second region that is adjacent to the another first region in the intersecting direction and that is planned to form another second wall serving as a width face among the four side wall portions when the sheet is assembled into the corrugated board box.