ObjectiveTo explore the impact of diabetes mellitus (DM) on characteristics of nosocomial infection (NI)．MethodsPatients with NI in a hospital between July， 2006 and June, 2008 were selected as studied subjects, and patients were divided into studied group (patients with DM) and control group (patients without DM), the similarities and differences in underlying diseases, infection sites, susceptible factors, invasive factors and pathogenic distribution between two groups were analysed.ResultsIn studied group, fewer patients  complicated with  tumor (P=0.00) ,more with urinary tract infection (P=0.00， OR=1.61), the use of chemotherapy (P=0.01),  glucocorticoid (P=0.00) and immunosupressive agents (P=0.01) were infrequent, more patients received  blood dialysis (P=0.00, OR=2.82) and developed Enterococcus infections (P=0.01, OR=2.06). ConclusionThere are certain impact of DM on characteristics of NI. The management of blood dialysis in patients with DM should be intensified and prevention of urinary tract Enterococcus infection should be paid attention.