Abstract Vanadyl alkylphosphates consisting of V4+ and P5+ were synthesized by the reaction of a solid mixture of V2O5 and V4O9 (2:3 in mol) with P2O5 in primary aliphatic (from C1 to C8), secondary aliphatic (C3 and C4), and alicyclic (C5) alcohols, and were characterized by means of elemental analysis, thermogravimetric analysis, X-ray diffraction, IR spectroscopy, and magnetic susceptibility. The chemical formulae of the products were determined to be VO(RO)x(HO)1−xPO3·(ROH)y (x = 0.5–0.7, y = 0.3–0.5 for primary aliphatic alcohols; x = 0.1–0.2, y = 0.4–0.9 for secondary aliphatic and alicyclic alcohols; and R = organic group). X-ray diffraction revealed that the compounds had a lamellar structure, where the organic groups existed as double layers with a tilt of about 56° against the basal plane. Magnetism and IR spectroscopy demonstrated that the construction of the basal planes in the vanadyl alkylphosphates was similar to that of VOHPO4·0.5H2O, which consists of V4+ dimers linked with PO4, except for vanadyl sec-butylphosphate, consisting of isolated V4+ monomers. Calcination of vanadyl methylphosphate and vanadyl cyclopentylphosphate brought about crystallites of (VO)2P2O7. These (VO)2P2O7 exhibited high selectivities to maleic anhydride (65–68%) for the selective oxidation of butane under a high concentration of butane (5.0%).