Abstract: The high activity copper oxide was prepared by complex precipitation method with the proper assistants，using copper sulfate and sodium hydroxide as the main raw materials.The effects of complex agents，assistants，and calcination temperature on the property of the product were studied in detail to determine the optimum conditions.The as-prepared product was characterized by SEM，XRD，and optical microscope.Results showed that the obtained product had not only a single copper oxide phase with uniform diversion，but also had a spherical-like morphology with diameter of about 1~2 μm.The chemical analysis showed that the activity copper oxide had a purity of more than 99%，and the dissolution time was about 15 s.

Key words: high activity copper oxide, complex precipitation, printed circuit board