The present invention relates to a fertilizer applicator having a fertilizer mixing function, and more specifically, to a fertilizer applicator having a fertilizer mixing function, configured to mix and discharge a desired amount of fertilizer when discharging the fertilizer stored in each of a plurality of hoppers by means of air blowing. To this end, according to the present invention, the fertilizer applicator, towed by power of a tractor, a rice planting machine, etc., comprises: a first hopper including two outlets formed in a lower side and air blowing pipes connected to the rear of the outlets, respectively； a second hopper including two outlets formed in a lower side and air blowing pipes connected to the rear of the outlets, respectively； an air blower configured to supply compressed air to the air blowing pipes； a first discharge pipe including one end connected to one outlet of the first hopper, and configured to forcefully transfer fertilizer discharged from the first hopper via the compressed air； a second discharge pipe including one end connected to the other outlet of the first hopper, and configured to forcefully transfer fertilizer discharged from the first hopper via the compressed air； a third discharge pipe including one end connected to one outlet of the second hopper, and configured to forcefully transfer fertilizer discharged from the second hopper via the compressed air； a fourth discharge pipe including one end connected to the other outlet of the second hopper, and configured to forcefully transfer fertilizer discharged from the second hopper via the compressed air； a first fertilizer discharge unit to which the other ends of the first discharge pipe and the third discharge pipe are connected so that the forcibly transferred fertilizer is mixed and discharged； and a second fertilizer discharge unit to which the other ends of the second discharge pipe and the fourth discharge pipe are connected so that the forcibly transferred fertilizer is
