Abstract: Objective To investigate the clinical and pathogenic features and drug sensitivity of anaerobic infection in patients with open injury of hands and forearms. Methods The clinical characteristics, laboratory indexes, and the results of pathogen identification and drug sensitivity test in 53 patients with anaerobic infection caused by the open injury of hands and forearms during 2015 and 2021 were retrospectively analyzed. Pathogens were identified by matrix -assisted laser desorption ionization time-of-flight mass spectrometry ( MALDI-TOF MS) and verified with 16S rRNA sequencing. The drug sensitivity test was performed using the Epsilometric test (E-test). Results Among the 53 patients, 52.8% were infected with one kind of anaerobe and one kind of non -anaerobic bacteria, and 88.7% were infected with one kind of anaerobe and one or more kinds of anaerobe and/ or non-anaerobic bacteria. A total of 26 species and 66 strains of anaerobes were isolated, and 75.8% of strains were isolated from the patients suffered direct or indirect bites. The types of drugs with a minimum inhibitory concentration ( MIC)≤0.5 μg/ mL against 23 strains of Gram-negative anaerobes belonging to the non-Bacteroides group included imipenem ( 96%, 22/23) , meropenem ( 96%，22/23) ，metronidazole ( 96%，22/23) ，piperacillin/ tazobactam (91% , 21/23)，and amoieilin/ clavulanic acid (87%, 20/23). Conclusion The mixed infection rate of anaerobic infection in the open injury of hands and forearms is high. The pathogens in the patients suffered direct or indirect bites are complex. The infections caused by Gram-negative anaerobes can be treated with imipenem, meropenem , metronidazole , piperacillin/ tazobactam and etc.