Some substiuents may influence a reaction by stabilizing a transition state or intermediate by becoming bonded or partially bonded with or without reagent to the reaction center. This behavior is called neighboring group effects. If the intermediate is stabilized in this way, the reaction rates are increased Therefore, the effects play an important role in producing regio-and stereoselectivity of a reaction. This review is described on the neighboring group effects in the field of natural product chemistry, especially steroids, terpeues, alkaloids and acetogenins.