Studies have shown that gut microbes can influence numerous aspects of human biology, and alterations in the function and composition of gut microbial flora (microbiota) play a major role in the pathogenesis of diverse human illnesses such as chronic inflammation, diabetes mellitus, and cardiovascular diseases. Gut microbes provide protection against pathogenic organisms, contribute to energy metabolism, serve a clear role in the development and modulation of the human gut immune system, and participate in nitrogen and micronutrient homeostasis by synthesizing amino acids and various vitamins. However, whether the composition of gut microbes is altered in human with renal failure has not been clearly demonstrated. Furthermore, whether alterations in the gut microbiota due to renal failure contribute to development of co-morbid conditions associated with CKD has never been examined. There are several lines of evidence to suggest that the gut microbiota is likely altered in patients with CKD. It has been established that protein assimilation in the small intestine is impaired in CKD .