The invention relates to an electro-deionization method and device for concentrating and purifying heavy metal wastewater synchronously, belonging to a wastewater treatment technique, which adopts first-stage two-section or first-stage multi-section electro-deionization device, wherein the inner sides of the positive and negative poles are arranged with corresponding pole protection chambers, the desalting chamber is filled with large-hole strong-acid strong-base mixed bed resin with narrow particles distributed; cation exchange film is adopted as the direction-turning film, after direction-turning, two adjacent concentration chambers are arranged continuously, both are separated by cation exchange film, simultaneously after direction-turning, the first concentration chamber is filled with large-hole mixed bed resin with the volume of cathode resin more than 50 percent, the heavy metal wastewater to be treated enters the desalting chamber and the concentration chamber in two paths, the heavy metal ion and cathode in the desalted water flow are transferred into the concentration chamber so as to obtain the desalted water, the concentrated water flow is partially circulated or closely circulated so as to obtain the concentrated liquid of metal wastewater, thereby recycling valence metals and pure water resources synchronously and realizing zero emission and resource treatment of wastewater. Compared with the prior art, the wastewater treatment process has higher separation efficiency, more reliable operation, more convenient operation, continuous process operation and no secondary pollution.