Abstract: Based on the one-dimensional elastic-plastic reactive hydrodynamic code SSS, the one-dimensional magneto-hydrodynamic code SSS/MHD is successfully developed. And calculation is done for cylindrical magneto cumulative generators (MC-1 device). The magnetic field diffusion into liner and sample tuber is analyzed, and the result shows that the maximum value of magnetic induction intension to cavity 0.2 mm in liner is only sixteen Tesla, while the one in sample tuber is several hundred Tesla, which is caused by balance of electromagnetism force and imploding one for the different velocity of liner and sample tuber. The curves of magnetic induction intension on axes of cavity and the velocity history on the wall of sample tuber are calculated according to the experiment results. The works in this paper accounting for that code SSS/MHD can be applied to experiment configures of detonation, shock and electromagnetism load and improvement of parameters. The experiment data can be estimated, analyzed and checked, and the physics course of correlative device can be understood deeply, according to SSS/MHD.