Coal-based low viscosity poly α-olefin produced by metallocene catalyst (mPAO) were characterized by gas chromatography (GC),thermogravimetry (TGA),pressure differential scanning calorimetry (PDSC),gel chromatography (GPC),rotating oxygen bomb method,and the performances were compared with commercial available PAO synthesized by long chains α-olefins.Results show that viscosity index of coal-based mPAO is up to 147,and viscosity-temperature capability is better than that of commercial available PAO.The pour point is generally 6 ℃ lower than the commercial available PAO,and low-temperature dynamic viscosity and low-temperature pumping viscosity are also lower than the commercial available PAO,indicating that coal-based mPAO has better low temperature performance.The flash points of the two products are the same,and both of them start rapid thermal degradation at 310 ℃.The coal-based mPAO has a higher complete decomposition temperature.The commercial available PAO has lower volatility.The shorter oxidation induction time indicates that the commercial available PAO has better oxidation stability.