Abstract: The performance of sealed dense plasma focus (DPF) tube was discussed. The movement of plasma player was simulated using 1-dimension snow-plough dynamics model, and the size and the shape of the electrodes were chosen. For the sealed tube, the special configuration and the vacuum processing were investigated. The sealed DPF tube, 26 mm×100 mm, can yield 10~(5) neutrons per pulse, with the power of 280 J.