The invention innovatively provides a method for treating caprolactam wastewater by using a salting-out method. The method comprises the following steps: precipitating partial organic matters in the wastewater by virtue of salting-out and flocculating actions, and further performing biochemical and incineration treatment on the reacted wastewater and precipitate respectively. The process method disclosed by the invention is low in energy consumption, low in investment and low in operating cost, and lots of caprolactam wastewater can be effectively and rapidly treated.