A three-dimensional object production method for shaping a three-dimensional object by laminating unit layers (25, 26) formed by ejecting droplets from a head, the head including a nozzle row in which a plurality of nozzles are aligned along a sub scanning direction which intersects perpendicularly to a main scanning direction of the head, the nozzle row being divided into two regions (A, B) in the sub scanning direction, wherein the second region is located downstream of the first region in the sub scanning direction and is adjacent to the first region, the method comprising: an allocating step of allocating the different regions (A, B) of the nozzle row to different pixel groups that are obtained by dividing pixel rows constituting a unit layer (25, 26) into two pixel row groups, each of the pixel row groups being constituted by pixel rows that are positioned at predetermined intervals in the main scanning direction; and a forming step of forming the pixel rows by the nozzles in each of the regions (A, B) forming one of the pixel row groups; wherein the unit layer (25, 26) is completed in two passes; the predetermined interval is one pixel row; and first pixel rows (25a, 26a) are formed in a first pass at the predetermined interval and second pixel rows (25b, 26b) are formed in a second pass in between the first pixel rows. the head including a nozzle row in which a plurality of nozzles are aligned along a sub scanning direction which intersects perpendicularly to a main scanning direction of the head, the nozzle row being divided into two regions (A, B) in the sub scanning direction, wherein the second region is located downstream of the first region in the sub scanning direction and is adjacent to the first region, the method comprising: an allocating step of allocating the different regions (A, B) of the nozzle row to different pixel groups that are obtained by dividing pixel rows constituting a unit layer (25, 26) into two pixel row groups, each of the pixel row groups being constituted by pixel rows that are positioned at predetermined intervals in the main scanning direction; and a forming step of forming the pixel rows by the nozzles in each of the regions (A, B) forming one of the pixel row groups; wherein the unit layer (25, 26) is completed in two passes; the predetermined interval is one pixel row; and first pixel rows (25a, 26a) are formed in a first pass at the predetermined interval and second pixel rows (25b, 26b) are formed in a second pass in between the first pixel rows. an allocating step of allocating the different regions (A, B) of the nozzle row to different pixel groups that are obtained by dividing pixel rows constituting a unit layer (25, 26) into two pixel row groups, each of the pixel row groups being constituted by pixel rows that are positioned at predetermined intervals in the main scanning direction; and a forming step of forming the pixel rows by the nozzles in each of the regions (A, B) forming one of the pixel row groups; wherein the unit layer (25, 26) is completed in two passes; the predetermined interval is one pixel row; and first pixel rows (25a, 26a) are formed in a first pass at the predetermined interval and second pixel rows (25b, 26b) are formed in a second pass in between the first pixel rows.