The invention discloses lubricating oil for bearings. The lubricating oil is prepared from the following components of modified base oil, succinate, dodecenylsuccinic acid ester, octyl diphenylamine, sorbitol, nanometer copper powder, lignin sodium sulphate, beta-sitosterol, cholesteryl nonanoate and poly(paraphenylene) terephthalamide. The lubricating oil disclosed by the invention is good in cooling properties and excellent in lubrication effects, and can be adapted to most application occasions, the antirust property of the lubricating oil can be greatly improved, the lubrication effects of the lubricating oil are also improved, the pour point is low, the friction coefficient of the lubricating oil at high temperature cannot be greatly changed, and the lubricating oil is high in stability, low in cost, good in viscosity index, high in abrasion resistant properties and long in service life. The lubricating oil disclosed by the invention has the characteristics of being light in color, high in polarity, good in fluidity and good in storage capability. The lubricating oil can be widely applied to mechanical lubrication, machinery can be well protected, besides, energy is saved, and consumption is reduced, so that the lubricating oil has wide application prospects.