GB/T 3671.1-1996 focusing on water-soluble dyestuff, specifies the determination method of its solubility and solution stability. The standard covers experimental instruments, reagent preparation and specific operation steps, and accurately determines the relevant performance by observing the degree of dyestuff dissolve and the change of solution state under specific conditions. For water-soluble dyestuff production, it can be used for mass control; in printing and dyeing applications, it can help to rationally select dyestuff, provide key technical basis for ensuring product mass and optimizing dyeing process, and promote the standardized development of water-soluble dyestuff industry.