a novel, lamellar type vanadium n-propylamino phosphate catalyst is synthesized and characterized by using various physicochemical techniques such as powder x-ray diffraction, scanning electron microscopy/energy dispersive x-ray analysis, thermogravimetry/differential thermal analysis, fourier transform infrared analysis, electron spin resonance spectroscopy, ultraviolet - visible diffuse reflectance spectroscopy, x-ray photoelectron spectroscopy, 31p magic angle spinning nuclear magnetic resonance spectroscopy and catalytic applications toward octahydroquinazolinone synthesis. it is found that the n-propylamine is present as sandwich between vanadyl phosphate layers. most of the vanadium is present as v4+ ions in tetrahedral co-ordination. vanadium n-propylamino phosphate catalyses octahydroquinazolinone synthesis more effeciently and the optimum conditions required for octahydroquinazolinone synthesis are, benzaldehyde (2 mmol), dimedone (2 mmol), urea (4 mmol), methanol + water (1:1, 5 ml) and catalyst (0.05 g). a plausible mechanism is also proposed.