Blood stream infections (BSI) due to carbapenem-resistant gram-negative bacilli (CR-GNB), especially Klebsiella pneumoniae carbapenemase (KPC) and New-Delhi metallo-β-lactamase (NDM) producers, are a major concern of public health, as they are associated with high morbidity and mortality. We conducted a single-center, retrospective, observational study at a tertiary-care, teaching Greek hospital, to determine the incidence, 30-day and overall, in-hospital, crude mortality, risk factors and efficacy of best available treatment options in patients with BSIs from KPC- or NDM-producing GR-GNB. During the one-year study period, from 1st January to 31st December 2023, we recorded 133 episodes of BSIs in 118 unique patients; 79 episodes were due to KPC-producing and 54 to NDM-producing CR-GNB. Our study showed relatively high incidence of BSIs by both KPC- and NDM-producing CR-GNB (0.49 and 0.31 episodes per 1000 patient-days respectively). We found high 30-day crude mortality rates for patients with BSIs due to KPC- producing CR-GNB (26.4 %), and NDM-producing CR-GNB (37%), while BSIs due to NDM-producing P. aeruginosa had the highest 30-day (47.1%) and overall (70.6%) in-hospital, crude mortality. Beta-lactam/beta-lactamase inhibitors as monotherapy or in combination with other active agents used to treat KPC-producing CR-GNB were associated with improved survival rates (p=0.009).