Abstract: Objective To explore the risk factors for the 28-day mortality of Klebsiella pneumoniae (KP) bloodstream infections (BSI) and its related influencing factors, thereby providing a scientific basis for the effective control of KP-BSI and improvment of patient outcomes. Methods From January 2018 to December 2024, a retrospective review was conducted on hospitalized patients aged 18 years old and above who were treated for KP-BSI at a tertiary hospital in Hangzhou. Logistic and cox regression analyses were performed to identify the epidemiological characteristics and the risk factors for the 28-day mortality associated with KP-BSI. Results A total of 123 patients with KP-BSI were included in this study, comprising 64 individuals infected with carbapenem-resistant Klebsiella pneumoniae(CRKP) and 59 individuals infected with carbapenem-susceptible Klebsiella pneumoniae (CSKP). Compared with CSKP bloodstream infection (BSI), patients with CRKP-BSI more frequently presented with chronic pulmonary disease (χ² = 4.29, P = 0.04), concomitant infections at other sites (χ²= 10.9, P < 0.05), and a higher prevalence of invasive procedures (central venous catheterization, mechanical ventilation, indwelling urinary catheter), glucocorticoid use, hemodialysis, and blood transfusion (all P<0.05). Mortality was significantly higher in BSI cases caused by CRKP compared to that caused by CSKP (37.50% vs 5.08%, P = 0.01). Cox regression analyses revealed that carbapenem resistance (HR=6.67，95%CI：1.48～30.08，P=0.01) and blood transfusion (HR=3.58,95%CI：1.15～11.19，P=0.03) were risk factors for the 28-day mortality in KP-BSI, while removal of central venous catheters after infection (HR=0.24,95%CI：0.08～0.67；P=0.01) was associated with a reduced risk for the 28-day mortality. Conclusion Carbapenem resistance was associated with mortality in patients with KP-BSI. Strengthening infection control measures targeting the identified risk factors for CRKP-BSI may improve patient prognosis.