Objective:To analyze the characteristics of adults (non-pregnant women) infected with Listeria monocytogenes and to provide evidence for diagnosis and treatment of this disease. Methods:Patients admitted in West China Hospital of Sichuan University between January 2008 and April 2020 with Listeriadisease were enrolled in this study. The clinical data of patients including age, symptoms, underlying diseases and prognosis, as well as the laboratory results of WBC, neutrophil ratio (N%), procalcitonin (PCT), interleukin-6 (IL-6) and C-reactive protein (CRP), were obtained for analyzing the clinical infection and prognosis characteristics of the patients. Results:A total of 57 patients were included, patients were 18-83 (52.8±15.9) years old, percent of over 60 years old patients accounted for 35.09% (20/57). The incidence rate in summer season was the highest (45.61%, 26/57). There were 48 cases with comorbidities, sepsis occurred in 31 cases and meningitis in 18 cases. The time of diagnosis of Listeriosis was (6.1±2.9) days. After diagnosis, the target therapy was applied: such as carbapenem (26.32%, 15/57) and penicillins (22.81%, 13/57). The levels of WBC (6.77 [2.99, 9.54]×10 9/L vs 10.23 [6.71, 16.55]×10 9/L), NLR (3.07 [1.66, 8.16] vs 11.26 [5.66, 20.08]) and CRP (40.7 [16.9, 91.9] g/L vs 92.8 [59.9, 142.7] g/L) were significantly lower after treatment than those before treatment in 47 hospitalized patients (all P<0.05). Thirty-eight patients were treated according to the guidelines, 33 cases improved, 2 cases had poor prognosis and 2 cases died. Conclusion:The main risk factors of Listeria monocytogenes infection in adults (non-pregnant women) are underlying diseases, especially autoimmune diseases and pulmonary infections. Penicillins can be used as the first choice for empirical therapy. Carbapenems and erythromycin serve as the combination medications during the full course of treatment.