PURPOSE: To form only a part planned as break-dividing part to the brittleness at the step of casting, in a manufacturing method of a bearing forming a bearing body and a bearing cap by break-dividing the bearing part integrally formed by casting.

CONSTITUTION: Molten metal is poured into the inner part in a mold 10 and casts a connecting rod crude casting providing a small end part as the bearing for piston pin at the one end and a large end part as the bearing for crank shaft at the other end. A sprue 14 in the mold 10 is arranged along the position planned as the division of the connecting rod crude casting. Since the solidifying speed of a cast iron near the sprue 14 is slow, the neighborhood of the sprue 14 is formed to the brittleness on the way of solidifying the connecting rod crude casting. The connecting rod crude casting is break-divided along the brittle position to manufacture the connecting rod composed of the connecting rod body and the connecting rod bearing cap.