The invention relates to injection machine lubricating oil. The injection machine lubricating oil comprises the following raw materials in parts by weight: 85-95 parts of mineral base oil, 15-25 parts of polyoxyethylene nonyl phenyl ether, 3-5 parts of hexachlorocyclopentadiene, 3-5 parts of dithioglycol, 5-10 parts of alkylated diphenylamine, 10-15 parts of graphene, 5-10 parts of modified zircon powder, 1-3 parts of methyl carbamate and 2-4 parts of benzimidazole. The lubricating oil has good abrasion resistance, rust resistance, heat stability, anti-foaming property, good seal compatibility, and high cleanliness, and can satisfy the requirement of an injection machine hydraulic system on lubricating oil. The lubricating oil has strong adhesive force so that oil is not easy to lose rapidly, the preparation method has the advantages of simpleness, convenient industrial production, and low cost.