Abstract: There are chemical interactions manipulated by plant secondary metabolites between plant and other organisms, which act as plant chemical defense on pests in cropping ecosystems. Under herbivore, infestation and competition, plants may trigger the defense mechanism producing and releasing allelochemicals to resist or inhibit the pests. Furthermore, the chemical mechanism of plant defense may be induced under pest stress. Recent studies have showed that there are manipulating interactions through allelochemicals in tri-trophic systems that include the host plant, herbivore, and parasitoid or predator. Besides allelopathy between crops and weeds, chemical recognition and information transfer may occur among inter-and intra-plant species. Clarification of chemical interactions between plant and other organisms not only widen the insight of species interactions, but also develop new strategy for pest control. This paper reviewed prospects for application in plant protection using chemical interactions between plant and other organisms.