A sintered oil retaining bearing has a bearing bore through which a rotary
shaft is inserted formed at a bearing main unit made of a porous sintered
alloy. The inner circumferential wall serving as the bearing bore includes
a center inner circumferential wall located at the center region of the
inner circumferential wall, and one end side inner circumferential wall
and other end side inner circumferential wall, located at one end side and
the other end side, respectively, of the center inner circumferential wall
in the direction of the rotary shaft. The center inner circumferential
wall has a blinded portion where the air permeability is not more than
0.3.times.10.sup.-3 darcy, and air permeability lower than that of the one
end side and other end side inner circumferential wall.