Abstract: In mid-August 2022, suckling piglets aged 7 to 15 days in the delivery room of a large-scale pig farm in Guangxi area suffered from severe diarrhea and vomiting, and even died, with a high mortality rate. In order to identify the cause and control the disease, the test first made a preliminary judgment on the cause according to the clinical symptoms and pathological examination results. Then the samples were collected, the viral pathogens and bacterial pathogens were further detected, and the bacterial pathogens were tested for drug sensitivity. Finally, according to the diagnosis, targeted treatment was carried out. The results showed that the intestinal wall of diarrhea suckling piglets was thin and translucent, and some intestinal segments were grayish yellow and grayish black. The intestinal wall was congested, and the contents were flocculent yellow or gray fluid. The stomach was filled with yellow fluid, and a small amount of curd could be seen. The preliminary conclusion was RV or PDCoV and Escherichia coli mixed infection. Further tests showed that Group A rotavirus（RVA） was positive in the samples, while porcine epidemic diarrhea virus（PEDV）, porcine transmissible gastroenteritis virus（TGEV） and porcine delta coronavirus（PDCoV） were negative. One strain of enterotoxigenic Escherichia coli（ETEC） was isolated from the samples. The isolate was sensitive to ceftriaxone, gentamicin and kanamycin, intermediated with parafenicol, doxycycline and enrofloxacin, and resistant to amoxicillin, temicosin, tevanistin and neomycin. Piglets with diarrhea in the delivery room were treated with 10% gentamicin at a dose of 2-3 mL/head; once a day for 3 consecutive days. After several days of treatment, the diarrhea of piglets was effectively controlled. The results showed that the main cause of severe diarrhea of suckling piglets in this farm was mixed infection of RV and ETEC, and the treatment measures had good effect.