2,4-Dichlorophenol is an important raw material for many pesticides and pharmaceutical intermediates. It can synthesize organophosphorus insecticides such as parathion, herbicide 2,4-D, 2,4-dibutyl ester, propafenone, 2,4-propafenone and new fungicide cyanobactam. It can be used as an important raw material of thiodichlorophenol in medicine.