The invention discloses a technology for processing wastewaters in a PCB industrial park. The technology comprises the following steps: 1, dividing the wastewaters into a comprehensive wastewater, a complex wastewater, a wastewater containing nickel and cyanogen, an acid waste, an organic waste, an organic wastewater, domestic sewage, and an accident wastewater according to water qualities of various wastewaters, respectively collecting them, and allowing them to enter different wastewater collection pools; 2, respectively carrying out heavy metal removal processing through a corresponding method according to water quality characteristics of the wastewater in each wastewater collection pool, wherein there is no need to carry out the heavy metal removal processing on the domestic sewage; and 3, processing all the wastewaters according to a biochemical processing process. According to the invention, the wastewaters in the whole PCB industrial park are detailedly classified, different present wastewater processing processes are adopted to carry out the heavy metal removal processing according to the different water quality characteristics of the wastewaters, and then the biochemical processing is adopted to further remove heavy metals from the wastewaters, so the COD (chemical oxygen demand) in each obtained discharged water is less than 40mg/L.