Traditional fermented foods are foods that have been acted upon by a consortium of microorganisms with improved nutritional values, organoleptic qualities, extended shelf-life, digestibility etc. Lactic acid bacteria are a large group of closely related bacteria that are involved in food fermentation and have similar properties such as lactic acid production. Some moulds and yeasts are also involved in food fermentation. The live microorganisms consumed together with fermented foods are called probiotics and they possess beneficial effects such as improvement of the health of intestinal tract, enhancement of the immune system, synthesis and enhancement of bio-availability of nutrients. Fermented foods have nutritional advantages as well as prophylactic and therapeutic potentials collectively known as functional properties. Functional foods are produced by the inclusion of probiotic organisms and prebiotics. This review looks at the functional properties of traditional fermented foods especially cereals.