Theory of Elasticity and Plasticity was used to analyzed stress of different deformation zone of part in hydromechanical deep drawing (HDD). HDD is a kind of advanced sheet metal forming method. Satisfying the need of adornment parts and auto parts and aiming at paraboloid chimney HDD with initial inverse pressure and variable blank-holder forces was studied by means of numerical simulation. The dynamic explicit analytical software DYNAFORM was employed to simulate the forming process to obtain major principal stress of the material. The blank holder force and hydraulic pressure influence on forming were studied. The load curve of blank holder force (BHF) and hydraulic pressure were optimized.