An agricultural irrigation method, system, device, and medium are provided. The method includes: acquiring a farmland condition data set of an area to be irrigated, and determining whether to generate a first irrigation instruction, where the first irrigation instruction is used to control a first solenoid valve and a first water pump on a first pipeline to be turned on, and a farmland is watered based on the first irrigation instruction; determining whether to generate a second irrigation instruction, where the second irrigation instruction is used to control a second solenoid valve and a second water pump on a second pipeline to be turned on, and the farmland is fertilized based on the second irrigation instruction; and determining whether to generate a third irrigation instruction, where pesticide is applied to the farmland based on the third irrigation instruction.