The present invention relates to a method for preparing an inosine-5&prime-monophosphate (IMP) fermented broth or a glutamic acid fermented broth as a raw material for preparation of a natural flavor, and more particularly to a method of preparing an IMP fermented broth or a glutamic acid fermented broth by a first fungal fermentation step and a second bacterial fermentation step, an IMP fermented broth and glutamic acid fermented broth prepared thereby, a method for preparing a natural flavor, which comprises preparing the IMP fermented broth or glutamic acid fermented broth, a natural flavor prepared thereby, and a food composition comprising the same. The IMP fermented broth and glutamic acid fermented broth may be used as raw materials for preparing natural flavors. In addition, the natural flavors are harmless and safe for use in the human body and may be added to food.
