The invention provides a dyeing method for sorghum pigment dye. The dyeing method comprises the following steps: (1) dyeing: carrying out dyeing on a cellulosic fiber fabric to obtain dyed cloth by using a water solution of sorghum pigment dye as dye liquor; and (2) color fixing: after soaking the dyed cloth in a color fixing solution, taking out the soaked dyed cloth for soaked rolling, then carrying out steam treatment, and then after soaking in a sodium hydroxide water solution, washing until neutral and drying, wherein the color fixing solution comprises 0.5 to 3 g/L of berberine, 0.5 to 2g/l of a water-soluble tannin extract and 0.5 to 2 g/L of wine. By adopting the method disclosed by the invention, the fabric dyed with the sorghum pigment is of soft luster, and then after color fixation with berberine, the water-soluble tannin extract and wine, the color fastness of the fabric can reach the national standard.