R Riboflavin is one type of vitamin B complex which is soluble in water, yellow, has a stable reaction towards heat in acid and neutral pH, easily reducible, and resistant to oxidizer compound. But on the other hand, riboflavin is easily damaged by alkali and ultraviolet light. Riboflavin in animal can be found in chicken liver, milk, cheese, oyster, meat and egg, meanwhile from vegetables, riboflavin can abundantly found in green vegetables and fruits like broccoli, spinach, asparagus, beans, avocado, and banana. From cereals and tubers it can be found in rice bran, brown rice, wholemeal flour, corn and red sweet potato. The number of Recommended Daily Allowance (RDA) of riboflavin for each person differs depending on sex, body size, activity, and specific physiological condition to achieve the optimal health level. Riboflavin acts as a coenzyme of flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) which helps the enzyme release the energy from carbohydrates, fats and proteins. Riboflavin is absorbed in the ileum by phosphorylation assisted by ATP as energy to be flavin mononucleotide and flavin adenine dinucleotide. Both of these substances are brought by the blood circulation to the liver, which later on will be distributed to the parts of the body in need of riboflavin. A disturbance of riboflavin’s metabolism can cause inflammation at the corner of the lips called cheilitis angularis and also inflammation of the tongue called glossitis. Riboflavin deficiency can be tackled by increasing the intake of foods that contain riboflavin. It can be given by peroral riboflavin or intramuscular (IM) when needed.