Herbivore-induced chemical defenses of plants vary according to the species of herbivores, plant tissues, and targeted chemical compounds. Additionally, environmental factors, such as soil nutrients, affect and induce plant chemical defenses to herbivores. Beneficial soil microorganisms may affect aboveground- herbivores positively by increasing food quantity, or negatively by attracting natural enemies of herbivores and promoting plant resistance. These effects are associated with phytohormones. In natural environment, plants would response simultaneously to biotic and abiotic stresses, which leads to crosstalk of phytohormone signaling networks and subsequently changes plant responses to stresses. This article discusses how soil microorganisms affect the interaction between plants and herbivores, and the influence of abiotic factors on the interaction.