All-perovskite tandem solar cells have been developed as a next-generation solar cell technology to surpass the efficiency limits of single-junction solar cells. By using perovskite materials with different bandgaps in the top and bottom cells, these tandem solar cells can effectively utilize a wider range of the solar spectrum. All-perovskite tandem solar cells have been focused as a next-generation solar cell due to their ability to achieve high efficiency while being manufactured through low-cost solution processing. This paper focuses on key components for improving the performance of all-perovskite tandem solar cells and essential components: wide bandgap perovskite solar cells, narrow bandgap perovskite solar cells, and charge recombination layers. The characteristics, main challenges, and strategies for overcoming these issues are discussed. For wide bandgap perovskites, efficiency is reduced by high trap densities and halide ion phase segregation. Improvement methods through additives and surface passivation are proposed to overcome these issues. In narrow bandgap perovskites, composition control and surface treatment techniques are being developed to reduce the oxidation of Sn-based materials and charge recombination in the perovskite. Additionally, the charge recombination layer is an essential component for efficient electron-hole recombination and minimizing optical losses, with materials such as transparent conductive oxides and ultrathin metals being used. These studies make a significant contribution to enhancing the efficiency and stability of all-perovskite tandem solar cells and suggest future research directions for commercialization.