3,6-Di-tert-butylcarbazole was synthesized under anhydrous and anaerobic condition by using 2-chloro-2-methylpropane as alkylation reagent and AlCl3 as catalyst with an isolated yield of 53%. The structure of the product was characterized by 1HNMR and 13CNMR. 3,6-Di-tert-butylcarbazole was used as an antioxidant agent of lubricating oil, and then it was compounded with an organic molybdenum addi-tive, organic molybdate (MoE) which was synthesized by our research group. Subsequently, 0.8% mass fraction of this compound was added into lube base oil II. The antioxidant performance of lube base oil II was evaluated by differential scanning calorimetry (DSC) dynamic method and rotary pressure vessel ox-idation test (RPVOT). DSC results showed that 3,6-di-tert-butylcarbazole effectively improved the oxida-tion stability and thermal stability of lube base oil II. The initial oxidation temperature of the sample by adding 3,6-di-tert-butylcarbazole was increased by 50.9℃, while that of lube base oil II by adding the compound of 3,6-di-tert-butylcarbazole and MoE was increased by 66.3℃. RPVOT results revealed that 3,6-di-tert-butylcarbazole could increase the oxidation induction period of lube base oil II to 2 times, the compound of it and MoE could increase the oxidation induction period to 2.5 times. The oil solubility test displayed that the introduction of tert-butyl groups on the carbazole benzene ring increased the solubility of carbazole in lube base oil II.