Disclosed herein is a lubricating oil for bearings comprising(a) a diester represented by General Formula (1) ##STR00001## wherein R.sup.1 and R.sup.2 are the same or different, and each represents a C.sub.3-C.sub.17 linear alkyl group; A represents a C.sub.2-C.sub.10 linear alkylene group or A represents a branched alkylene group consisting of a linear alkylene group, the linear alkylene group being the principal chain, and one or more alkyl groups (branches) bonded to the linear alkylene group, wherein the total number of carbon atoms of the linear alkylene group and the one or more alkyl groups is 3 to 10; with the proviso that when A is a branched alkylene group and has two or more alkyl groups, the two or more alkyl groups are not bonded to the same carbon atom; or a mixture of the diester with an additional base oil and(b) at least one member selected from the group consisting of phenol-based antioxidants and amine-based antioxidants, and optionally containing(c) at least one member selected from the group consisting of Phosphorus-based compounds and aliphatic linear monocarboxylic acids, and further optionally containing(d) at least one member selected from the group consisting of benzotriazole-based compounds and gallic acid-based compounds.