The Bi3.95Er0.05Ti3O12 (BErT) thin films are prepared on the indium-tin-oxide (ITO)-coated glass substrates at room temperature by the pulsed laser deposition technique. The research results show that, the BErT thin film prepared under a low deposition oxygen pressure possesses a dense and uniform surface without cracks, and an amorphous structure. Under a 3 Pa deposition oxygen pressure, the BErT thin film has a thickness of about 180 nm and shows outstanding dielectric characteristics, such as a dielectric constant of 52 at room temperature and a dielectric loss of 0.025 at the test frequency of 1 kHz. Meanwhile, the dielectric properties of the BErT thin film show a relative stability when the frequency, the voltage and the temperature change and also has a relatively high optical transmissivity in the visible light regime.