Abstract: The present invention relates to the formulation and process of preparing a functionalized urethane alkyd resin. More particularly, the invention relates to a siliconized urethane alkyd resin obtained from an alkyd based on semi drying/drying Oils or their fatty acids having high iodine number of 120-170 (gm I2/100 gm) followed by grafting of epoxy alkyl alkoxy silane or silanol functional silicone resin into the alkyd backbone and subsequent urethanization of the organosilane grafted alkyd. Siliconized urethane alkyd thus obtained were incorporated in solvent borne pigmented coating compositions and found suitable for preparing air drying 1 pack coatings providing excellent corrosion resistance, weathering and mechanical properties when applied on variety of substrates such as mild steel, corroded mild steel, other metals, alloys, glass, wood and cementitious etc.