Due to the high preparation cost and complex process of traditional crystalline silicon solar cells, people are studying new solar cell power generation technologies. Metal halide perovskite solar cells have become the most promising category in the next generation of solar cells because of their high power conversion efficiency, extremely low cost, and simple manufacturing technology. So far, perovskite solar cells based on rigid substrates have achieved over 26% power conversion efficiency. Flexible semi-transparent perovskite solar cells have attracted the attention of researchers due to their wide range of application scenarios. This article first introduces the basic principles of perovskite solar cells. Then, the research related to transparent electrodes in flexible semi-transparent perovskite solar cells is discussed, including key technologies of transparent electrodes. Afterwards, the application of flexible semi-transparent solar cells in greenhouse agriculture is analyzed and introduced. Finally, the further developments of flexible semi-transparent perovskite solar cells are summarized and prospected.