Perovskite solar cells have received great attentions as the next-generation photovoltaic device and the power conversion efficiency undergoes a continuous increase. The optoelectric properties of perovskite solar cells not only intimately connects to the perovskite film， but also has a direct connection with the device structure， interface， and the optical design. In this paper， our attention is focused on the surface optical properties. By introducing an antireflection layer on top of perovskite solar cells， it is anticipated to lower the reflection loss at the surface and enhance the power conversion efficiency. After studying the effect of microstructure on the transmittance， it is found that the antireflection layer with grating pattern can further increase the transmittance. Experimental results show that the introduction of antireflection layer can to some extent boost the power conversion efficiency of perovskite solar cells. At last a brief discussion about the involved mechanism of antireflection layer is provided.