Background: Burn patients are predisposed to infection because of the loss of skin barrier protection and low immunity. This study aims to evaluate the risk factors of post-burn infections due to beta-lactam and carbapenem-resistant bacteria (CR) isolated from a major burn unit.Methods: The descriptive study was conducted at Jinnah Hospital Lahore’s Burn and Reconstructive Surgery Centre (JB & RSC) and the Institute of Microbiology and Molecular Genetics (MMG), University of the Punjab, Lahore. The clinical specimens of wound swabs, including the age, gender, socio-economic status, residence, occupation, hospital stay, wards, burn degree, total burnt surface area (TBSA%), etiology of burn, and other factors were recorded. Antimicrobial susceptibility testing (AST), ESBL and CR screening (Beta- lactam and carbapenem resistant bacteria) were performed using CLSI guidelines 2017.Results: The most dominant strain was Pseudomonas spp. 26.5% (n=106), followed by 15% (n=60) Klebsiella spp., and 7.5% (n=30) Acinetobacter spp. with ESBL-producing strains. Compared to nosocomial infections, community-acquired infections were observed in 314 (78.5%) patients with more ESBL production. There was a significant relation between burnt people having an age of ≤ 29 years with ESBL (p=0.985) and carbapenemases (p=0.694) infections. None of the other factors, like low socioeconomic status and more hospital stays had a significant correlation (p > 0.05).Concluded: It has been concluded that MDR gram-negative strains play a serious role in burn infections and demand suitable methods to decrease their number. Pseudomonas spp. was the most common post-burn infection causing bacteria. Unfortunately, a high frequency of burn infections was observed in the patients at a young age.Keywords: Post burn infections; Gram negative; MDR; Beta- lactam; Carbapenem resistant