A bearing device includes a bearing member provided with a circumferentially extending sliding surface and a housing holding the bearing member on an inner circumferential surface thereof. The bearing member is provided with a bearing outer peripheral surface on one side thereof facing the housing. The bearing outer peripheral surface is surface roughened. The housing is provided with a housing inner peripheral surface on one side thereof facing the bearing member. The housing inner peripheral surface is surface roughened. When a mean height Rc of a roughness curve element of either of the bearing outer peripheral surface and the housing inner peripheral surface is Xμm, the remaining other of the bearing outer peripheral surface and the housing inner peripheral surface has a material ratio Rmr (Xμm) of roughness curve being equal to or less than 10% in at least one measurement direction.