Objectives: This study aimed to analyze clinical characteristics and outcomes of critically ill patients with multiple myeloma (MM) admitted to the intensive care unit (ICU) and identify predictors of poor short-term prognosis. Methods: Data for patients with MM admitted to the ICU were extracted from the Medical Information Mart for Intensive Care III database. The risk factors leading to the ICU and hospital mortality were evaluated using logistic regression analysis. Results: Of 126 patients identified, 17 (13.5%) and 37 (29.4%) died in the ICU and hospital, respectively. Patients with ICU mortality showed higher median blood urea nitrogen (57.0 vs. 29.0) and poorer Acute Physiology Scores (APS, 70.0 vs. 46.0) than did surviving patients on the day of ICU admission. In-ICU deceased patients had higher proportion of mechanical ventilation (64.7% vs. 26.6%) and vasopressor use (64.7% vs. 17.4%) at admission and positive pathogenic culture during ICU stay (58.8% vs. 19.3%). The APS and positive pathogenic culture were independent prognostic factors for ICU mortality, while risk factors for hospital mortality included higher APS and relapsed/refractory disease. Conclusion: The short-term prognoses for patients with MM admitted to the ICU were mainly determined by the severity of organ failure, infection, and disease status. [ABSTRACT FROM AUTHOR]