type of λ/4～λ/2 broadband antireflective coating has been developed by sol-gel dipping method with tetrabutylorthotitanate and tetraethoxysilane (TEOS) as precursors. This antireflective coating possesses smooth and even surface,its average roughness is estimated having the value of RMS (1.201) and RA (0.934),and the specific scratch-resistant is good. Most -OH groups are eliminated at the temperature near 200 ℃. The average transmission of both-coated K9 substrate is increased 6.6% higher than uncoated one in the spectra from 400 nm to 700 nm. The antireflective coating is expected to coat amplifier blastshields of "Sheng-Guang: facility for enhancing the pumping efficiency of amplifiers