Gut microbiota, formerly called gut flora, is the name given today to the microbial population living in human intestine. It has the largest number of species in comparison to other body parts. In humans, the gut flora was established at childhood through one to two years after birth. The relationship between some gut flora and humans is not only commensal, but also a mutualistic relationship, in a way that intestine support the growth of healthy gut flora that  provides a barrier to pathogenic organisms. Some beneficial human gut microorganisms ferment dietary fiber into short-chain fatty acids (SCFAs), such as acetic and butyric acid. In additional, play a role in synthesizing vitamin B and vitamin K as well as metabolizing bile acids and sterols. There are several factors affecting the change on human gut flora varieties over time such as, the diet type and composition, the bacterial infections, the human lifestyle, physical activity and antibiotic or surgical treatment. The key factor between them is the diet types and its composition. It was suggested the frequency of bacteria present in the intestine significantly associated with the dietary patterns. Thus, this article describes current indication regarding the links between gut microbiota varieties and dietary patterns throughout life. In addition, the importance of microbiota-diet interactions extensively studied by modern new bioinformatics tools and molecular based techniques to demonstrate the potential microbiota-diet interactions which could change future approaches to nutrition in healthy and diseased human bodies.