To smoothly move a sprocket and an idler from the center part to a rubber part where there exist no core metal, without being vertically moved, and reduce vibration with respect to an operator.

In an inner circumference driving type rubber crawler in which the crawler is provided with each core metal 10 buried in rubber, each pair of angle parts 12 projected at the right and left sides while being crosswise in a row at certain pitch, each pair of angles parts 12 projected at the right and lefts sides while each core metal 19 is being held in between at its center part, and with each driving projection 24 which is of continuous length in the width direction rather than the longitudinal direction of each core metal, and is formed out of each angle part 12, and of each rubber member 23 covering the longitudinal direction of each angle part, and each driving pin is engaged with each driving projection 24 so as to allow driving power to be transmitted, in the inner circumferential surface at the center part of the rubber crawler, the inner circumferential surface 26 of the rubber crawler between the adjacent core metals 10, is projected to the inner circumferential side of the rubber crawler 20 rather than the inner circumferential surface at the center part 13 of each core metal located between the driving projections 24.