Ceftazidime-Avibactam (CAZ-AVI) is a new antimicrobial against carbapenem-resistant Klebsiella pneumoniae. The aim of the study is to examine the cost-effectiveness of CAZ-AVI compared to colistin-meropenem (COL+MEM) in Colombia.A decision tree model was developed from health-care system perspective assuming a 30-day time horizon. The clinical course was simulated based on treatment response between 48 and 72 hours, and the duration of the treatment was 7-14 days. Cost inputs were extracted from a published Colombian manual tariffs and official databases, expressed in 2019 dollars (USD).In the base case analysis, CAZ-AVI was associated with reduced mortality, length of hospital stay and fewer add-on antibiotics, resulting in an increase of 1.76 QALYs per patient versus COL+MEM and incremental costs associated in CAZ-AVI were $2,521 higher per patient compared to COL+MEM ($755 versus $3,276). The incremental costs were partially increased due to the lower mortality rate observed with CAZ-AVI. The incremental cost-effectiveness ratio was estimated to be $3,317 per QALY. In the probabilistic sensitivity analysis, with a willingness to pay above $2,438, CAZ-AVI has higher probability of being cost-effective.CAZ-AVI demonstrates cost-effectiveness as a treatment for Carbapenem-resistant Klepsiella pneumoniae infections by reducing the number of deaths and increasing QALYs.Previous studies and surveillance programs from Colombia have reported prevalence of pathogens and the antimicrobial susceptibility of infections caused by multidrug-resistant Gram-negative bacteria. The health authorities have to consider and plan adequate surveillance systems in order to predict the resistance type and in choose the optimal antibiotics when infections occur.