The source, the composition and the harm of iron and steel pickling waste water are introduced, and the state of art, the principle and the advantages/disadvantages on treating the iron and steel pickling waste water both domestic and abroad were analyzed. The present situation of acid recycling and metals recovery for the iron and steel pickling waste water is reviewed, and acid recycling methods including diffusion dialysis, membrane techniques, evaporation and spray roasting, and the metals recovery methods such as neutralization and precipitation, crystallization, ion exchange and so on are emphasized. These technology can achieve the acid recycling and metals recovery in order to make good use of resources.