Background: Extended spectrum beta lactamases (ESBLs) producing Enterobacteriaceae cause infections that are often reported in both hospital and community setting. These infections are on the increase and jeopardize the achievement of modern medicine because of their clinical implications. There is need for surveillance measures to be taken, both by the health care personnel and the community at large. Methodology: We examined 330 diarrhea stool samples from children below the age of 5 years and processed them. A total of 96 (29%) samples were identified as Klebsiella pneumoniae out of the bacteria isolated. Identification of ESBL was done and 42 K. pneumoniae isolates were tested for the occurrence of bla CTX-M, bla OXA, bl aTEM and bla SHV resistant genes by PCR, gel electrophoresis and visualized by UV illumination. Results: Our results revealed that bla CTXM was the most frequent ESBL type 42 (100%), followed by bla TEM in 41 (97.6%) isolates and bla SHVin38 (90.4%) of the isolates. None of the tested isolates were found to be encoding bla OXA. There was occurrence of more than one gene in most of the isolates. The double combination was detected in bla CTX-M/ bla TEM (9.5%) and bla CTXM/SHV (2.4%). A triple combination was noted bla-TEM/ bla SHV/ bla CTX-M (88%). Conclusion: Our results indicate that there is Presence of Beta lactam genes associated with antimicrobial resistance among the K. pneumoniae isolates from Mukuru Slum, Kenya. The predominant ESBL genotype in Mukuru slums, Kenya was bla CTX-M followed by bla TEM and bla SHV respectively. There is need for surveillance measures to be taken so as to control the spread among the community.