The invention discloses a plant composite foliar fertilizer which is composed of raw materials of, by mass: 20-25 parts of honey, 8-10 parts of amino acid, 12-15 parts of KH2PO4, 10-12 parts of Ca(NO3)2, 0.2-0.4 parts of anhydrous ZnSO4, 0.1-0.2 parts of anhydrous CuSO4, 1.5-2.5 parts of anhydrous FeSO4, 0.8-1.2 parts of anhydrous MnSO4, 9-10 parts of EDTA, 0.05-0.10 parts of anhydrous (NH4)2Mo2O7, 1.7-2.3 parts of anhydrous H3BO4, 0.1-0.2 parts of gibberellin, 0.15-0.25 parts of cytokinin, 0.2-0.4 parts of sodium naphthalene acetate, 0.8-1.2 parts of sodium nitrophenolate, 0.4-0.6 parts of diethyl aminoethyl hexanoate, 4.5-5 parts of 70% -75% ethanol, and 30-33 parts of neutral water. A preparation method of the fertilizer comprises the steps that: trace elements are complexed by using EDTA; life active substances are dissolved by using ethanol; all the raw materials are dissolved in heated neutral water; the obtained material is stood; precipitated impurities are removed; and the obtained product is packaged. The plant composite foliar fertilizer provided by the invention is rich in various components required by plant growth, and is characterized by small top dressing dosage, long effectiveness, and substantial production increasing effect. The plant composite foliar fertilizer provided by the invention is sprayed in various important periods of crop growth and development. With the fertilizer, base fertilizers except nitrogen fertilizer can be eliminated before sowing.