We propose a new RANS model for turbulent channel flows imposed wall-normal magnetic fields with heat transfer. This proposal model can be ensured adequate MHD effects on model functions and parameters in the turbulent eddy viscosity and the production minus destruction term of the epsilon-transport equation. With this new proposal model, the Nusselt number of several Prandtl number fluids (Pr = 0.025, 5.25 and 25) under the magnetic fields can be predicted in the range of less than 5% errors compared with the DNS database. The application possibility of this model is in the ranges of Ha2/Reτ2 less than 0.05.