Abstract: The membrane decoloring and activated carbon decoloring of sulfate polymyxin B were compared. The results showed that the decoloration rate of sulfate polymyxin B was 86% when it was treated by membrane decoloring under the conditions of pressure of 25 kgf/cm2, pH of 2.5, feeding temperature of 50 ℃. The decoloration conditions with activated carbon A were as follows： decoloration time of 50 min, feeding temperature of 55 ℃ ,the addition amount of activated carbon was 2.5% of feed solution, its decoloration rate was up to 75%.