A flame hole structure for a combustion apparatus having a plurality of flame holes for forming a flame, the flame hole structure comprising: a lean flame hole part having at least one lean flame hole extending along a lengthwise direction that is a direction perpendicular to a release direction of a lean gas, as a flame hole to release the lean gas; and a rich flame hole part having a pair of rich flame holes provided on opposite sides of the lean flame hole part with respect to a width direction that is a direction perpendicular to the release direction and the lengthwise direction, the pair of rich flame holes extending along a direction parallel to the lengthwise direction, as flame holes to release a rich gas, wherein the lean flame hole includes at least one bent lean flame hole portion bent toward the center of the lean flame hole part along the width direction and horizontal lean flame hole portions provided on opposite sides of the bent lean flame hole portion with respect to the direction parallel to the lengthwise direction and extending along the direction parallel to the lengthwise direction, characterized in that the rich flame hole includes at least one protruding rich flame hole portion protruding toward the bent lean flame hole portion to correspond to the bent lean flame hole portion and horizontal rich flame hole portions provided on opposite sides of the protruding rich flame hole portion with respect to the direction parallel to the lengthwise direction and extending along the direction parallel to the lengthwise direction to correspond to the horizontal lean flame hole portions, and wherein in a region extending from at least any one horizontal rich flame hole portion to another horizontal rich flame hole portion through the adjacent protruding rich flame hole portion, the rich flame hole part is provided to be spaced apart from the lean flame hole part by substantially the same interval. a lean flame hole part having at least one lean flame hole extending along a lengthwise direction that is a direction perpendicular to a release direction of a lean gas, as a flame hole to release the lean gas; and a rich flame hole part having a pair of rich flame holes provided on opposite sides of the lean flame hole part with respect to a width direction that is a direction perpendicular to the release direction and the lengthwise direction, the pair of rich flame holes extending along a direction parallel to the lengthwise direction, as flame holes to release a rich gas, wherein the lean flame hole includes at least one bent lean flame hole portion bent toward the center of the lean flame hole part along the width direction and horizontal lean flame hole portions provided on opposite sides of the bent lean flame hole portion with respect to the direction parallel to the lengthwise direction and extending along the direction parallel to the lengthwise direction, characterized in that the rich flame hole includes at least one protruding rich flame hole portion protruding toward the bent lean flame hole portion to correspond to the bent lean flame hole portion and horizontal rich flame hole portions provided on opposite sides of the protruding rich flame hole portion with respect to the direction parallel to the lengthwise direction and extending along the direction parallel to the lengthwise direction to correspond to the horizontal lean flame hole portions, and wherein in a region extending from at least any one horizontal rich flame hole portion to another horizontal rich flame hole portion through the adjacent protruding rich flame hole portion, the rich flame hole part is provided to be spaced apart from the lean flame hole part by substantially the same interval.