The invention relates to a pesticide spraying device with the pesticide dispensing function. The device comprises a base, a supporting rod, a cross rod, a pesticide box, a water storage box, a mixingbox, a water inlet pipe, a pesticide inlet pipe, a driving mechanism, a quantifying mechanism and a spraying mechanism, the driving mechanism is arranged on the supporting rod, the quantifying mechanism is arranged on the driving mechanism, and the spraying mechanism is arranged at one side of the mixing box. According to the pesticide spraying device with the pesticide dispensing function, the quantifying assembly is driven by a driving assembly to operate, quantitative mixing of pesticide liquid is achieved, meanwhile, the spraying mechanism is driven to operate, spraying of the pesticide liquid is achieved, and compared with an existing pesticide spraying mechanism, the device can achieve quantitative mixing and spraying of the pesticide liquid through one output end, so that energy issaved; and through linkage of the quantifying mechanism and the spraying mechanism, online mixing of the pesticide liquid is achieved, meanwhile, a pure mechanical mechanism is adopted for linkage, use of sensors and other electronic elements is avoided, the stability of the device is improved, the service life of the device is prolonged, and the practicability is improved.