In January 2017，some calves between the age of 10 to 20 days suffered from diarrhea，bloody stools，dyspnea and other symptoms in a large-scale dairy farm in Shandong Province，some of them died suddenly. According to epidemiological investigation and autopsy，Clostridium perfringens was initially suspected as the cause. Then related samples were collected and a series of tests were conducted. Based on histopathologic examination，isolation and identification of bacteria，biochemical test and 16s and toxin gene detection，the cause of this epidemic was finally confirmed as type A Clostridium perfringens infection. The pathogenicity of the isolated strain and intestinal contents from dead calves were analyzed，results showed that both of them had relatively strong pathogenicity. Besides，drug sensitivity tests showed the isolated Clostridium perfringens was extremely sensitive to Penicillin，Cefotifuran，Enoxacin，etc. After reasonable administration of clinical drugs，the epidemic was controlled timely.