Abstract: With Mohair salt mine，in Qinghai Province as raw material，the dissolution laws of K+ and Na+ from the salt mine were studied by orthogonal experiments.After a certain time of dissolution mine，the influences of three factors，ratio of liquid to solid，sodium chloride content in the solvent，and magnesium chloride content in the solvent on the contents of  K+ and Na+ in the liquid were investigated by orthogonal test method and the experiment results were analyzed with SPSS. The test results showed the influencing order for K+ and Na+ contents was：liquid to solid ratio>sodium chloride in solvent>magnesium chloride in solvent.The optimum conditions for the mineral dissolution were confirmed as follows：liquid-solid ratio was 1∶0.5，the content of sodium chloride was 50%（mass fraction，and same below） of its saturation in the solvent，the content of magnesium chloride was 3% in the solvent.Under optimal conditions the content of KCl was more than 1.2% which met the relevant requirements，and the small amount of dissolved NaCl also reached the requirements that the salt mine skeleton will not collapse.

Key words: potassium mineral dissolving, orthogonal test, SPSS