A three-dimensional printing device, comprising: a printing tank to accommodate a powder material and including an opening in at least a portion thereof; an ejector facing the opening of the printing tank to eject a curing liquid to cure the powder material toward the opening; and a controller to control the ejector to eject the curing liquid; wherein the ejector includes: a first nozzle string including a first plurality of nozzles side by side in a predetermined first direction to eject the curing liquid; a second nozzle string including a second plurality of nozzles side by side in the first direction to eject the curing liquid; a third nozzle string including a third plurality of nozzles side by side in the first direction to eject the curing liquid; a fourth nozzle string including a fourth plurality of nozzles side by side in the first direction to eject the curing liquid; a first head including the first nozzle string and the second nozzle string; and a second head including the third nozzle string and the fourth nozzle string, the second head being spaced away from the first head in a second direction perpendicular to the first direction; the first plurality of nozzles, the second plurality of nozzles, the third plurality of nozzles, and the fourth plurality of nozzles are located in the first nozzle string, the second nozzle string, the third nozzle string, and the fourth nozzle string at a density of 1200 dpi or lower in the first direction, respectively; the first nozzle string and the second nozzle string are spaced away from each other by a distance shorter than 5 mm in the second direction; the first nozzle string and the third nozzle string are spaced away from each other by a distance equal to, or longer than, 5 mm in the second direction; and the controller is configured or programmed to, in at least a portion of a time duration in which the ejector ejects the curing liquid, cause the curing liquid to be ejected from the first plurality of nozzles of the first nozzle string and the third plurality of nozzles of the third nozzle string but not to be ejected from the second plurality of nozzles of the second nozzle string. a printing tank to accommodate a powder material and including an opening in at least a portion thereof; an ejector facing the opening of the printing tank to eject a curing liquid to cure the powder material toward the opening; and a controller to control the ejector to eject the curing liquid; wherein the ejector includes: a first nozzle string including a first plurality of nozzles side by side in a predetermined first direction to eject the curing liquid; a second nozzle string including a second plurality of nozzles side by side in the first direction to eject the curing liquid; a third nozzle string including a third plurality of nozzles side by side in the first direction to eject the curing liquid; a fourth nozzle string including a fourth plurality of nozzles side by side in the first direction to eject the curing liquid; a first head including the first nozzle string and the second nozzle string; and a second head including the third nozzle string and the fourth nozzle string, the second head being spaced away from the first head in a second direction perpendicular to the first direction; a first nozzle string including a first plurality of nozzles side by side in a predetermined first direction to eject the curing liquid; a second nozzle string including a second plurality of nozzles side by side in the first direction to eject the curing liquid; a third nozzle string including a third plurality of nozzles side by side in the first direction to eject the curing liquid; a fourth nozzle string including a fourth plurality of nozzles side by side in the first direction to eject the curing liquid; a first head including the first nozzle string and the second nozzle string; and a second head including the third nozzle string and the fourth nozzle string, the second head being spaced away from the first head in a second direction perpendicular to the first direction; the first plurality of nozzles, the second plurality of nozzles, the third plurality of nozzles, and the fourth plurality of nozzles are located in the first nozzle string, the second nozzle string, the third nozzle string, and the fourth nozzle string at a density of 1200 dpi or lower in the first direction, respectively; the first nozzle string and the second nozzle string are spaced away from each other by a distance shorter than 5 mm in the second direction; the first nozzle string and the third nozzle string are spaced away from each other by a distance equal to, or longer than, 5 mm in the second direction; and the controller is configured or programmed to, in at least a portion of a time duration in which the ejector ejects the curing liquid, cause the curing liquid to be ejected from the first plurality of nozzles of the first nozzle string and the third plurality of nozzles of the third nozzle string but not to be ejected from the second plurality of nozzles of the second nozzle string.