Quinazolines show a number of biological activities. The molecular manipulation of promising lead compound is still a major line of approach for the discovery of new drugs. Combination of two or more moieties into one is a common procedure of manipulation and this can probably result in the increase of biological activity and removal of untoward side effects. In this present work effort was made to synthesis twelve tetrahyroquinazoline derivatives by using different aldehydes. The synthesized compounds evaluated for physical characterization like, molecular weight, melting point, Rf value and solubility. The structure of the synthesized compounds was confirmed by spectral analysis like IR, NMR and Mass. The synthesized compounds were subjected for evaluation antioxidant activity. The compound 4a1 and 4a3 showed more promising antioxidant activity against reducing power assay, phosphomolybdate method. The tetrahydroquinazoline and its derivative have shown better antioxidant activity compared to the standards like BHA and ascorbic acid respectively.