Abstract: Biosynthesis of ABA in higher plants comprises a series of chemical re actions starting with mevalonate(MVA) in cytoplasm or yruvate_thiamin triphosphate(TPP) in chloroplast. Besides stresses and developmental changes, some endogenous enzymes such as zeaxanthin epoxidase(ZE),9_cisepoxycarotenoid dioxygenase(NCED) and aldehyde oxidase(AO) play key roles in the regulation for ABA biosynthesis. This article introduced the new progresses on the regulation of ABA biosynthesis in higher plants.