Objectives A etiological investigation and effective diagnosis and treatment of acute deaths of goats in a goat farmer in Pu'er City, Yunnan Province, was conducted to provide references for disease diagnosis in farming goat. Methods Emergency epidemiological investigation, on-site investigation, pathological autopsy, and laboratory testing were conducted on 116 goats including 40 adult goats aged over 12 months and 76 lambs aged 6-9 months to make comprehensive analysis and diagnosis. Results The results of pathological autopsy showed that there were hemorrhages in the lungs, kidneys, and gastrointestinal tract of the sick goats, with the heart having changes similar to heart failure. The results of testing nucleic acid showed that all 5 samples of goats were positive for Clostridium welchii in nucleic acid. Conclusions The illness and death of goats this time was caused by Clostridium welchii, with a high possibility of infection from grazing in the wild. The illness and death were resulted from the low level of farming and management, the decrease in temperature, and the decline in immunity of goats without vaccination with the triple and four prevention vaccines. Proper management of farming and immunization should be implemented. Grazing on rainy days should be reduced. Early reporting of any unusual circumstances and timely isolation of sick goats are necessary to effectively control the spread of the diseases.