Jar-tests were used to study the removal effect of organics by MIEX pre-treatment from Yangtze River raw water, in which molecular weight, fractionation, UV scan, disinfection by-products, DOC and UV254 were used to estimate the removal effect. The results showed that organics in raw water were mainly composed of low-molecular weight and hydrophilic fraction, which accounted for above 50% of total organics. Above 35% DOC was removed by MIEX pretreatment with a dosage of 10 mL/L and contact time of 15 min, which due to the removal of low molecular weight and hydrophilic organics. The results of UV scan showed that organics which had high adsorption between 190 nm and 250 nm were significantly removed by MIEX pretreatment, while the part that had high adsorption on wavelength above 250 nm could be removed similar to coagulation alone.