Abstract: The three dimensional numerical calculation is applied to the gas solid two phase flow in different temperature fields in the rectangular pipe. The N S equations of the three dimensional turbulence are derived with the CFD software. The results show that the velocity field of the particle is changed in different temperature fields. From the distribution of the particle’s volume concentration, it is concluded that the difference of themophoresis force existing in the temperature leads to the difference of particles’ concentration distribution. The law of the different particles’ concentration distribution in the temperature field is obtained.