The invention discloses a method for preparing a ZnGaNO-polymer self-cleaning hybrid membrane with an interfacial polymerization method. The preparation method is characterized by comprising the following steps: S1, adding ZnGaNO particles into an aqueous phase solution containing a first reaction monomer and a surfactant, performing ultrasonic uniformization, directly immersing a porous supporting membrane into the aqueous phase solution, then taking out the porous supporting membrane and discharging the excessive solution on the surface; S2, immersing the supporting membrane which adsorbs the first reaction monomer and the ZnGaNO particles into an oil phase solution containing a second reaction monomer, performing interfacial polymerization, and generating a ZnGaNO particle-containing aromatic polymer functional skin layer on the surface of the porous supporting membrane after reacting for a period of time; and S3, performing heat treatment on the ZnGaNO particle-containing aromatic polymer functional skin layer and rinsing to obtain the ZnGaNO-polymer self-cleaning hybrid membrane. The invention also relates to the ZnGaNO-polymer self-cleaning hybrid membrane obtained by the method.