Objective To study the properties of hard anodic oxidation coatings on 2A12 aluminum alloy prepared in the electrolyte of sulphuric acids and hybrid acids separately,in order to find out the influencing mechanism of hybrid acids on hard anodic oxidation process of 2A12 aluminum alloy, and provide method to enhance the coating corrosion resistance. Methods The properties of hard anodic oxide coatings prepared in different electrolytes were analyzed and characterized by thickness, micro-hardness, SEM morphology, polarization curve and AC impedance spectroscopic to investigate the influence of different electrolytes on the performance of hard anodic oxidation coatings on 2A12 aluminum alloy. Results The phenomenon of hard anodic oxide coatings on 2A12 aluminum alloy prepared in electrolyte of sulphuric acids such as ablation, non-uniform distribution of thickness and micro-hardness can be resolved by active adsorption of organic acids in electrolyte of hybrid acids, and the thickness distribution range was 35 ~38 μm, the micro-hardness distribution range was 386 ~ 407HV0. 05. The polarization curve and the EIS analysis showed that the corrosion potential of unsealed and sealed coating was -619. 93 mV and -74. 69 mV separately, the barrier layer resistance of unsealed and sealed coating was 1. 4×105 Ω·cm2 and 2. 376×106 Ω·cm2 separately, which indicated that corrosion resistance can be enhanced and improved by sealing. Conclusion Hard anodic oxide coatings on 2A12 aluminum alloy can be stably prepared in electrolyte of hybrid acids, and the coating should be sealed.