Nano-tailoring the shape and dimensions of the parabolic antireflective structure predicted by simulation has been successfully carried out to fabricate monolithic high-performance antireflection (AR) polymer films. The average total reflectivity from an artificial antireflection film is lowered down to 0.64% at a wavelength range of 400 nm to 800 nm, which appears to be the best antireflection performance ever reported for transparent polymer antireflection films.