In this paper, the action principle of inorganic salts for dyeing was analyzed. Status of low salt or salt-free dyeing research was discussed comprehensively. The specific methods were analyzed and summarized from four areas which were researched on reactive dye of low salt (salt-free) dyeing,study on salt substitutes, research on fiber modified and application of new progress, new technology of low salt dyeing. Advantages and disadvantages of every method were discussed. Reasonable suggestions and comments were provided for the application of low salt or salt-free dyeing.