The temperature field during solidification process was simulated by adopting 2D un stable heat transfer equation with an enthalpy formulation for latent heat. The solidified grain structure formation for K4169 superalloy was simulated by means of continuous nucleation model and kinetic model of dendrite tip growth （KGT model）. Coupling temperature field simulation with grain structure formation simulation

the characteristic parameters of solidified grain structures of the superalloy

including grain density and average grain size

were calculated. And the visualization of solidified grain structure by the computer has been performed. The results showed that the simulated results coincided well with the experimental results.