In order to effectively improve the liquidity of the high viscosity and low mobility oil，the performances of the amphoteric viscosity reducer AVR with intellectual property were studied systematically，and the influences of alkalis and polymers were investigated. Experimental results indicated that the viscosity reduction efficiency was more than 82%，and the system could change the wettability of oil-wet surface，and had good ability of stripping oil film within 41 seconds，and could achieve lower interfacial tension（IFT）1.8×10^-2 mN/m. Alkali could help to enhance the performances of the amphoteric viscosity reducer AVR. Especially for adding Na₂CO₃ system，the viscosity reduction efficiency increased to more than 85%，the stripping film time shortened to 10 seconds，and ultra-low IFT（less than 1.0×10^-2mN/m）could achieve within 15 minutes rapidly，and IFT still showed a downward trend with the extension of time. When the polymer concentration was in the range of 100—500 mg/L，the viscosity reduction efficiency of the AVR systems was more than 80%，and the systems could still reach ultra-low IFT. The molecules of the viscosity reducer AVR could form three-dimensional network structure through the association，so that the solution had certain viscosity to improve the role of the swept volume. The AVR solution had good shear resistance capacity，and the viscosity retention rate was 86% after high speed shear（5000 r/min）in 60 seconds；the AVR solutions could pass through the nuclear pore membrane（more than 0.2 μm）and viscosity retention rate was more than 90%，which indicated that the AVR solution had good injectivity.