A clean micelle fracturing fluids based on long chain amine oxide surfactant and counter-ion salts was obtained, and the rheological properties, thermal stability and related factors of the system were studied. The results showed that, the optimal formulation was 2% LAO + 3% NaSal, and the temperature resistance limit value of the system was of 120℃. The viscosity of the optimal system was kept above30mPa·s after sheared for 1 hour at the shear rate of170 s^-1 at the temperature of 110℃. The rheological results showed that the 2%LAO +3%NaSal fracturing fluids was characteristic of significant viscoelastic, thixotropic and shear thinning properties, and possessed excellent proppant-suspension property. Gel breaking experiments proved that when the volume ratio of the fracturing fluidings to the crude oil was lower than40:1, the fracturing fluids could be broken completely after mixed with the crude oil, and the viscosity of the broken fluids was less than 3 mPa·s.