Thermal deformation process of H62 brass is studied, multi-scale simulations of macro-forming property and microstructure distribution are carried out for the hot-extrusion process of double cups part with flange utilizing numerical simulation technology, the process parameters are determined and the microstructure of extruded parts is predicted. The constitutive equation of H62 brass under high temperature deformation is established with isothermal compression test, and the results indicate that the flow stress accords to Arrhenius hyperbolic sine functions. The model of microstructure evolution during hot-deformation is founded and the influence of process parameters on microstructure is revealed. The microstructure prediction on extruded part shows that the simulated results agree well with the experimental results. The high-quality products are obtained using the optimal process parameters.