The extensive use of diesel engines has led to significant emissions of pollutants, especially soot particles, which pose serious risks to both the environment and human health. At present, developing catalysts with low-temperature activity, low cost, and high stability remains the core challenge in eliminating soot from diesel engine exhaust. This paper first reviews the mechanisms of soot catalytic oxidation. Based on these mechanisms, the current design directions for soot catalysts are summarized and discussed. On the one hand, the effects of modification methods such as doping, loading, and solid solution on the performance of manganese-based catalysts are reviewed from the perspective of intrinsic activity. On the other hand, the research progress on manganese-based catalysts with specific morphological structures for soot oxidation is explored. Following the identification of design strategies, the commonly used preparation methods to achieve these designs are also outlined. Finally, the paper highlights the challenges associated with manganese-based catalysts in soot catalysis and discusses future research and development directions.