Thermochromic VOthin film was synthesized on glass slide substrates by reactive RF magnetron deposition (= 450 °C) following annealing (= 400 °C). The method of synthesis results in the formation of preferred orientation vanadium dioxide with acicular nano-structure. The transmittance of monolayer VOthin film reaches to 67% in the visible light region. This study provides a novel method to improve visible transmittance of VOthin films, which boosts their practical applications in smart windows.