The invention provides an intelligent spraying method based on image processing and a spraying robot based on image processing. Through the method, the spraying robot can correctly distinguish specific crops and weeds and carry out targeted spraying according to the distribution condition of the crops and the weeds needing to be sprayed, that is, the spraying robot sprays weed killer on the weeds and sprays corresponding disinfectant and other pesticides on the crops, and consequently intelligent spraying without human interference is achieved. Meanwhile, a wireless video transmission mode is additionally adopted, and a worker can monitor and control the spraying robot by holding a monitor in hand. Thus, the intelligent spraying robot not only reduces the labor intensity of the workers and spraying cost but also reduces the use quantity of the pesticides and pesticide residues in the soil environment and has an immeasurable significance in improving spraying intellectualization and modernization of agriculture and accelerating agriculture precision in our country.