A sprocket support body comprises an external spline configured to be engaged with an internal spline of a bicycle sprocket arrangement. The external spline includes a plurality of external-spline driving surfaces configured to transmit a rotational driving force between the sprocket support body and the bicycle sprocket arrangement in a circumferential direction. The plurality of external-spline driving surfaces includes at least four first external-spline driving surfaces and at least one second external-spline driving surface. The at least four first external-spline driving surfaces are respectively arranged on at least four of nine first external-spline driving positions equally arranged in the circumferential direction about a rotational center axis at a first external-spline pitch angle which is equal to 40 degrees. The at least one second external-spline driving surface is offset from the nine first external-spline driving positions in the circumferential direction about the rotational center axis.