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Tungstovanadophosphoric heteropoly acid H 6 PW 9 V 3 O 40 •(13.81 ± 0.13)H 2 O (abbreviated as PW 9 V 3 ) has been synthesized by the stepwise acidification and the stepwise addition of element solutions. The crystal structure was determined from single crystal X-ray diffraction. The complex crystallizes in the space group R3̅ m, with a = 16.4374 (9) Å, b = 16.4374 (9) Å, c = 25.3866 ( 14) Å, α = 90°, β = 90°, γ = 120°, V = 5940.20 Å, and Z = 6. The product possesses Keggin structure, and its conductivity was 1.730 × 10 −2 S•cm −1 at 26 °C and 75% relative humidity by electrochemical impedance spectroscopy (EIS) measurement. Two conducting systems were prepared with a mixture of as-synthesized PW 9 V 3 and organic polymers [polyvinylpyrrolidone (PVP) or polyethylene glycol (PEG)] at the weight ratio 80:20. The hybrid materials exhibit high proton conductivities with 7.110 × 10 −3 and 1.050 × 10 −2 S•cm −1 (PW 9 V 3 /PEG) at 26 °C and 75% relative humidity, respectively. Their activation energies of proton conduction are 15.23 and 13.67 kJ•mol −1 , which are lower than that of pristine heteropoly acid (25.68 kJ•mol −1 ). Their mechanisms of proton conduction are also proposed.