This paper starts with the response of plants to aluminum toxicity, systematically summarizes the regulatory effects of biochar on the pH and aluminum forms of acidic soil, the mechanisms and influencing factors of biochar in improving the structure and fertility of acidic soil, and the impact of biochar on the structure and function of microbial communities in acidic soil. It also explores the potential mechanisms of biochar in alleviating aluminum toxicity, and looks forward to future research on potential problems in the process of biochar improving acidified soil.