The present invention relates to a functional feed additive for abalone spats, in which a Polygala tenuifolia extract, a Rubus coreanus extract, a Cynanchum wilfordii extract, a Phlomis umbrosa extract, and a Saururus chinensis extract, which are natural herb medicines with verified safety, are contained as active ingredients, and plant composite extracts and ascidian extracts, such as spirulina, are mixed as a composition for growth promotion to increase the production of an insulin-like growth factor (IGF), wherein the functional feed additive has advantages of immunity enhancement, disease prevention, growth promotion, and the like, when added to feed for abalones at an appropriate ratio according to the growth stage. In the case where young abalones are fed with the feed mixed with the functional feed additive of the present invention, animal protein are replaced with vegetable protein at a considerable ratio according to the efficacy of medicinal herbs and marine algae which are mixed at a proper ratio, and thus the body components is influenced to allow the young abalones to maintain similar body components to natural abalones, thereby improving the adaptability of the young abalones to the change of feeding environment, healthily growing the abalones without infection with diseases during the growing period of abalone spats, and improving the body weight gain, thus maximizing the efficiency of the feed through an increase in the feed intake rate. Furthermore, the functional feed additive of the present invention is hardly soluble in water, thereby enabling eco-friendly culturing through a reduction in the pollution of marine environments.본 발명은 종래 안전성이 입증된 천연 한방 생약제로서 원지 추출물과 복분자 추출물, 백하수오 추출물, 속단추출물 , 삼백초 추출물을 유효성분으로 포함하여 효과적으로 IGF(성장인자) 생산량을 증가시키는 성장촉진용 조성물로서 식물복합추출물과 스피룰리나 등 해조류 추출물이 혼합 조성된 전복 치패용 기능성 사료첨가제로서 성장단계별로 전복 사료에 적정 비율 첨가시 면역력 증강, 질병예방, 성장촉진 등의 장점을 지니고 있어 본 발명 기능성 사료첨가제를 혼합한 사료를 어린 전복에게 급여하게 되면 적당한 비율로 배합된 한약재 및 해조류의 효능에 따라 동물성 단백질을 식물성 단백질로 상당 비율
