A crawler propelling device comprising: a crawler belt, the crawler belt including a belt main body made of rubber material, cored bars embedded in the belt main body at predetermined intervals in a belt circumferential direction, and a holler-guiding cored bar projection protruding from an inner circumferential surface of the crawler belt; and a driving sprocket for providing the crawler belt with rotational power in the belt circumferential direction, wherein the crawler belt has engaging recesses provided on the inner circumferential surface of the crawler belt to be engageable with driving claws of the driving sprocket, each of the engaging recesses being positioned between the cored bars in the belt circumferential direction, wherein the driving claws are provided on an outer circumferential portion of a disk-shaped member of the driving sprocket at predetermined intervals in a circumferential direction of the disk-shaped member to be engaged into the engaging recesses formed in the crawler belt, the outer circumferential portion of the disk-shaped member being overlapped with a moving trace of the cored bar projection as viewed from a lateral side, wherein each of the driving claws is projected laterally from a disk surface of the disk-shaped member in a belt width direction intersecting the disk surface of the disk-shaped member, and wherein the engaging recesses and the driving claws have respective contact surfaces extending in opposition at a distance to each other, and a projecting contact portion is provided on one of the contact surfaces at a position offset in the belt width direction from a position opposed to the cored bar projection, the projecting contact portion projecting in a direction to reduce a distance to the other of the contact surfaces, compared with the distance between the respective contact surfaces. a crawler belt, the crawler belt including a belt main body made of rubber material, cored bars embedded in the belt main body at predetermined intervals in a belt circumferential direction, and a holler-guiding cored bar projection protruding from an inner circumferential surface of the crawler belt; and a driving sprocket for providing the crawler belt with rotational power in the belt circumferential direction, wherein the crawler belt has engaging recesses provided on the inner circumferential surface of the crawler belt to be engageable with driving claws of the driving sprocket, each of the engaging recesses being positioned between the cored bars in the belt circumferential direction, wherein the driving claws are provided on an outer circumferential portion of a disk-shaped member of the driving sprocket at predetermined intervals in a circumferential direction of the disk-shaped member to be engaged into the engaging recesses formed in the crawler belt, the outer circumferential portion of the disk-shaped member being overlapped with a moving trace of the cored bar projection as viewed from a lateral side, wherein each of the driving claws is projected laterally from a disk surface of the disk-shaped member in a belt width direction intersecting the disk surface of the disk-shaped member, and wherein the engaging recesses and the driving claws have respective contact surfaces extending in opposition at a distance to each other, and a projecting contact portion is provided on one of the contact surfaces at a position offset in the belt width direction from a position opposed to the cored bar projection, the projecting contact portion projecting in a direction to reduce a distance to the other of the contact surfaces, compared with the distance between the respective contact surfaces.