An inkjet printing method of an array substrate, an array substrate, and a display device are disclosed. The array substrate includes n kinds of sub-pixels; and the inkjet printing method includes: recording a solvent volume required for inkjet printing of an i-th kind of sub-pixel as Vi; calculating an Xi value for each kind of the n kinds of sub-pixels, in which Xi=Vi/V1, and V1 refers to a solvent volume required for inkjet printing of a first kind of sub-pixels; taking a greatest common divisor of the Xi values of the n kinds of sub-pixels, and recording the greatest common divisor as G; and dividing the i-th kind of sub-pixel into Xi/G subunits with equal areas, and performing inkjet printing on each of the subunits of the i-th kind of sub-pixel with a solvent volume of V1*G to form a film layer.