A combination structure of a piston and piston rings suitable for a spark ignition engine , said engine comprising the piston fitted in a cylinder in the spark ignition engine and a combination of a plurality of piston rings assembled to the piston , the combination structure comprising the combination of the plurality of piston rings including a first compression ring assembled at a position closest to a combustion chamber , a second compression ring assembled at a position close to the combustion chamber next to the first compression ring , an oil ring assembled at a position farthest from the combustion chamber , and a third compression ring assembled at a position between the second compression ring and the oil ring , wherein when an axial width of the first compression ring is h1 , an axial width of the second compression ring is h1 , an axial width of the third compression ring is h1 , and an axial width of the oil ring is h1 , h1 ≥ h1 and h1 ≥ h1 , wherein, when h1(TOTAL) = h1 + h1 + h1 + h1 , 10 mm ≥ h1 (TOTAL) ≥ 3,1 mm, the piston has an outer peripheral surface that is formed with a first ring groove in which the first compression ring is fitted, a second ring groove in which the second compression ring is fitted, a third ring groove in which the third compression ring is fitted, and an oil ring groove in which the oil ring is fitted, when a length from an end face of the first ring groove on a combustion chamber side to an end face of the oil ring groove on a crank chamber side in an axial direction of the piston is Lp, 23.5 mm ≥ Lp ≥ 5. 1 mm, and when a length, in the axial direction of the piston , of a second land portion (L2) that is a region defined by the first ring groove and the second ring groove in the outer peripheral surface of the piston is Lp2, and a length, in the axial direction of the piston , of a fourth land portion (L4) that is a region defined by the third ring groove and the oil ring groove is Lp4, Lp2 > Lp4. the combination structure comprising the combination of the plurality of piston rings including a first compression ring assembled at a position closest to a combustion chamber , a second compression ring assembled at a position close to the combustion chamber next to the first compression ring , an oil ring assembled at a position farthest from the combustion chamber , and a third compression ring assembled at a position between the second compression ring and the oil ring , wherein when an axial width of the first compression ring is h1 , an axial width of the second compression ring is h1 , an axial width of the third compression ring is h1 , and an axial width of the oil ring is h1 , h1 ≥ h1 and h1 ≥ h1 , wherein, when h1(TOTAL) = h1 + h1 + h1 + h1 , 10 mm ≥ h1 (TOTAL) ≥ 3,1 mm, the piston has an outer peripheral surface that is formed with a first ring groove in which the first compression ring is fitted, a second ring groove in which the second compression ring is fitted, a third ring groove in which the third compression ring is fitted, and an oil ring groove in which the oil ring is fitted, when a length from an end face of the first ring groove on a combustion chamber side to an end face of the oil ring groove on a crank chamber side in an axial direction of the piston is Lp, 23.5 mm ≥ Lp ≥ 5. 1 mm, and when a length, in the axial direction of the piston , of a second land portion (L2) that is a region defined by the first ring groove and the second ring groove in the outer peripheral surface of the piston is Lp2, and a length, in the axial direction of the piston , of a fourth land portion (L4) that is a region defined by the third ring groove and the oil ring groove is Lp4, Lp2 > Lp4. <EOS>