The solidification characteristics of centrifugal casting Ti47Al2Nb1Cr1W0.2Si alloy was studied by means of the isothermal quenching technology and optical microscope (OM) observation. The solidus and liquidus of the alloy were determined to be 1465 °C and 1520 °C, respectively. The Ti47Al2Nb1Cr1W0.2Si alloy car valves were cast with different superheats by the single step centrifugal casting process. The influence of the superheat on the fraction of fully filled mould and oxygen content of valve was studied. The results show that the best superheat for casting car valves is 160 °C.