A new series of eighteen complexes of oxovanadium(IV) with the Schiff bases of 4-aminoantipyrine, viz. 4-[(N-benzalidene)amino] antipyrine (BAAP), 4-[(N-4-dimethyl-aminobenzalidene) amino] antipyrine (DABAAP) and 4-[(N-4-methoxybenzalidene)amino] antipyrine (MBAAP) with the general formula VOX2.nL (X = Cl, Br, I, NO3, NCS, n = 1; X = ClO4, n = 2 and L = Schiff base) have been prepared and characterized on the basis of analytical conductance, molecular weight, magnetic moment, infrared and electronic spectral data. The infrared data of the complexes reveal the bidentate nature of the ligands and coordinated to pyrazolone oxygen and azomethine nitrogen atoms. The probable coordination number of the central metal is found to be five. Thermal stabilities of the complexes have been studied through thermogravimetric analysis.