Abstract: 　Objective　To explore the clinical characteristics including the morbidity, clinical manifestation, and pathogens of late-onset sepsis (LOS) in very low birth weight (VLBW) infants in neonatal intensive care unit (NICU). Methods　Clinical data of all VLBW infants in NICU from January 2011 to December 2013 were collected. According to the results of blood culture, the VLBW infants diagnosed with LOS were divided into confirmed LOS group and clinical LOS group. The morbidity, clinical manifestations, common pathogens, and drug sensitivity of LOS were retrospectively analyzed. Results　In 226 VLBW infants, there were 117 cases of LOS with the morbidity at 51.8%. Forty-five infants were confirmed to have LOS by blood culture, accounting for 19.9% (45/226); another 72 infants were diagnosed with clinical LOS, accounting for 31.9% (72/226). The rates of tachycardia and temperature fluctuation in confirmed LOS group were higher than those in clinical LOS group, and there were significant differences (P<0.05). There were 51 strains of pathogenic bacteria, with 32 Gram-negative bacteria (62.7%), 16 Gram-positive bacteria (31.4%), and 3 fungi (5.9%). The common pathogenic bacteria were Klebsiella pneumoniae and coagulase negative Staphylococcus, the most of which were multidrug-resistant bacteria. Conclusions　The incidence of LOS in VLBW infants is high. The main clinical manifestations are sudden changes in breathing, heart rate, mental state, and skin color. Although these manifestations are not specific, they could serve as early warning. The common pathogenic bacteria are Klebsiella pneumoniae and coagulase negative Staphylococcus, and both of them are multidrug resistant.