Embedded material shell was prepared using wax grid with 8? mesh. The effects of micro-alloy elements B, Y, Mn and Er on the mold filling capacity of Ti-46Al-8Nb melt were studied. The results showed that the fluidity and mold filling property of Ti-46Al-8Nb melt was improved to some extent by B, Y, Mn and Er addition. Especially, 0.5Y and 1Mn addition had significant improvement on the mold filling capacity of the alloy, which increased the filling rate by 54.5% and 48.5% respectively. The effect of 0.1Er, 0.5B and 1B addition on the mold filling capacity of the alloy was not so remarkable, with the filling rate increasing by 3.0%, 4.5% and 5.3% respectively.