The theoretical foundations of plant biological protection are outlined. Practical use of developed methods of environmentally safe suppression of the number of harmful species is shown. Described are the main agents of biological control of pests, diseases and weeds of crops (microorganisms, entomoacariphages, biologically active substances). An assessment of the current level of development of plant biological protection is given. The strengthening of the role of biological methods in the integrated protection of plants that most fully meet the goals of environmental protection and human health is shown.