Background. Multidrug-resistant (MDR) clones of Klebsiella pneumoniae (Kpn) have been increasingly documented in community-acquired and nosocomial infections all around the globe. Extended-spectrum β-lactamases (ESBLs) are a rapidly evolving group of β-lactamase enzymes derived from SHV genes by mutations. This research work aimed to investigate and analyze the widespread prevalence of Kpn antibiotic resistance in different areas of the southern part of Bangladesh. Methods. This particular study was executed and implemented by using 501 clinical samples or isolates from two different hospitals in Chattogram. The disk diffusion method was used to detect Kpn’s sensitivity to 16 antibiotics in a drug susceptibility test. By using the PCR technique, the widespread prevalence of antibiotic-resistant gene blaSHV-11 was studied. Sequencing along with phylogenetic analysis was utilized to verify isolates with the blaSHV-11 gene. Results. Almost all of the Kpn isolates were spotted to be antibiotic-resistant. These Kpn isolates were resistant to β-lactams, aminoglycosides, and quinolones at high levels. The spatial analysis displayed that infections involving Kpn were more common in the urban areas (70%) than in the rural areas (30%). Neonates had substantially higher levels ( p < 0.001 ) of resistance to multidrug than other age groups. Cefepime was identified as the most frequent antibiotic-resistant to all age groups (56.68%). The highest numbers of resistant isolates (36.92%) were found in urine samples. The ESBL gene blaSHV-11 was found in 38% isolates. Conclusion. The significant frequency of MDR Kpn harboring β-lactamases and AMR genes strongly suggests the requirement to develop effective antimicrobial resistance control and prevention measures in Bangladesh.