Objective: To detect the serum levels of interleukin-3 (IL-3) in patients with sepsis and its clinical significance. Methods: One hundred cases of sepsis in our hospital from December 2017 to December 2018 were divided into a non-shock group (n=69), a shock group (n=31), a survival group (n=79), and death group (n=21). Fifty healthy people in the same period were enrolled as the control group. Blood and urine samples were collected for the measurement of IL-3 and other related biochemical indicators. Acute physiology and chronic health evaluation II (APACHE II) and sequential organ failure assessment (SOFA) were recorded as indicators to assess the severity of the disease. Results: Serum levels of IL-3 in sepsis group were significantly higher than those in healthy control group (P<0.01), while serum levels of IL-3 in shock group were higher than those in non-shock group (P<0.01), and serum levels of IL-3 in death group were higher than those in survival group (P<0.01). Serum levels of IL-3 was positively correlated with APACHE II score (r=0.67, P=0.02) and SOFA score (r=0.59, P=0.03). Serum levels of IL-3 was an independent risk factor for death events in sepsis patients (P=0.03); the ROC curve area under which IL-3 level judged the prognosis of sepsis death was 0.88, sensitivity was 0.86, specificity was 0.72 (P=0.03). Conclusion: Serum levels of IL-3 in sepsis patients are elevated and correlated with the severity of the disease. It can be used to evaluate the prognosis of sepsis.