In order to prevent the pollution of colchicine for drinking water and explore a method of on line monitoring and early warning system, the effects of various factors on CL system were optimized, and an on line monitoring and early warning system for drinking water polluted by colchicine was constructed. The results showed that the optimum condition for colchicine detection were as follows: pump speed was 1 mL/min, the pH value of luminol was 13.20, the concentration of luminol was 3.00×10–4 mol/L, the concentration of potassium ferricyanide was 3.00×10–4 mol/L. The linear range of this method was 5.0×10–3–1.0 mg/L with a detection limit of 3.01×10–5 mg/L and relative standard deviation of 2.78% (n=11). This system could be applied to real time monitoring and early warning for drinking water polluted by anthropogenic or abiogenetic factors with high sensitivity and good operability.