It was confirmed that the concentration of potassium carbonate in discharging agents with benzaldehyde sodium bisulfite (BASB) was a very important factor affecting the dischargeabilities of vinylsulfonyl reactive dyes such as C.I. Reactive Orange 16 (0-16), C.I. Reactive Blue 19 (B-19) and C.I. Reactive Black 5(Bl-5). Putting colors, C. 1. Reactive Orange 13 (0-13) and C.I. Reactive Blue 15 (B-15), in discharging pastes with potassium carbonate were generally stable but showed a little decrease of color strength of 0-13 resulting from alkaline hydrolysis. When putting color and ground color were in the relationship of complementary color, lightness and saturation of putting color were decreased because of slight residue of ground color in spite of high whiteness. The putting color differences between discharge printing and direct printing decreased with increasing the concentration of potassium carbonate, and it was expected that the dyes of putting colors could contribute to the dischargeability. On the other hand, colored discharge printing of Bl-5 showed large color differences of putting colors due to its poor dischargeability. It was also found that steaming conditions greatly affected the dischargeability of Bl-5.