Structure of bearing housing of cylinder block

A structure of bearing housings of a cylinder block comprises aluminum alloy for constituting the whole cylinder block and a plurality of fiber reinforced metal (FRM) areas. The FRM areas are formed by integrally casting a sheet-like preform containing reinforced metal fibers with aluminum alloy. A plurality of such sheet-like preforms are separately provided in a bearing housing in an axial direction of a crankshaft.