In April 2020，the suckling piglets were infected with a disease characterized by low spirits and increased temperature of body，and a number of suppurative necrosis scabs on skins of head，neck，back and limbs in a swine farm in Weihai City of Shandong Province，with a morbidity of 32.43% and a mortality of 16.67%. In order to confirm the pathogens and identify all causes，blood and pus in the affected parts of dead pigs were collected for biochemical test，drug sensitivity test and colloidal gold test. The results showed that the samples were positive for porcine circovirus by colloidal gold test，and the results of biochemical test were consistent with the characteristics of Staphylococcus，which was confirmed as the secondary staphylococcal infection with porcine circovirus disease according to the above clinical symptoms and autopsy lesions. Based on the results of drug sensitivity test，the infected pigs were injected with highly sensitive Ceftiofur sodium，then all internal and external delivery rooms were sprayed with disinfectant. Meanwhile，all pigs in the population were vaccinated with inactivated porcine circovirus type II vaccines. Ultimately，the disease was effectively controlled. In addition to the immunosuppressive diseases that should be concerned and controlled，the management for environmental hygiene and pig production should also be strengthened by large-scale farms. As a conclusion，some references were hereby provided for the diagnosis and treatment of the disease.