Abstract: Comparison of autoionization and dielectronic capture with dielectronic recombination in ion population in Ge plasma was given. Solving the coupled rate equations, the contribution factors from Flike and Nelike ions on the lower and the upper laser level of 19.6 and 23.6 nm lines, and the ionization rates of Nalike and Nelike ions were studied． Further more, inversion factor and gain at 19.6 and 23.6nm lines were discussed ．