Since the first report on a long-term durable solid-state perovskite solar cell with a PCE of 9.7% in 2012, perovskite solar cell has been intensively researched. As a result PCE approaches almost 20% in about 2 years. In this talk, opto-electronic properties of perovskite materials and high efficiency device engineering will be discussed. Photoferroic property of methylammonium lead iodide is observed, which is significantly dependent on perovskite crystal size. Size-dependent photoferroic effect is found to influence on I-V hysteresis. Interfaces play important roles in photovoltaic performance, where the blocking layer/perovskite interface affects photocurrent but voltage is influenced by the perovskite/HTM interface. Imperfect blocking layer is however found to deteriorate voltage significantly according to ZnO nanorod study. Photo-generated electrons are transported both in perovskite and TiO2 as observed in TiO2 nanohelix based perovskite solar cell, where injection into TiO2 depends on surface area of TiO2 helicies. By interfacial and morphological optimization, power conversion efficiency (PCE) over 17% is routinely attained. Furthermore, feasibility study shows that hybridization of perovskite solar cell with a conventional semiconductor solar cell can lead to PCE approaching 30%.