In order to quantify the influence degree of biochar on soil humus content, a meta-analysis of literature was used to integrate the changes of soil texture and pH, biochar pyrolysis temperature, application amount and duration, with soil humus content without adding biochar as a control. The results showed that adding biochar significantly increased humic acid and humin content in sand humus by 18.6% and 92.2%, respectively, compared with not adding biochar. The contents of humic acid in neutral and alkaline soils were increased by 12.5% and 13.7% respectively. The application of biochar with cracking temperature of 500-600℃ increased the contents of humic acid, fulvic acid and humin in soil by 22.6%, 14.1% and 68.5%, respectively. Under the biochar application of 20-40 t/hm², the contents of humic acid, fulvic acid and humin in soil were significantly increased by 23.7%, 6.9% and 84.6%, respectively. The content of humic acid increased significantly in 3 months of biochar application, with an average increase of 29.5%. The increase gradually decreased from 3 months to 1 year, and gradually increased after 1 year. The humin content of biochar increased the most at 6 months, with an average of 72.2%. With the extension of biochar application time, the increase of humin content in soil decreased gradually. In summary, the application of biochar with a cracking temperature ranging from 500 to 600℃ exhibits significant short-term improvement effects on sandy and loam soils under neutral or alkaline conditions. Moreover, these effects gradually stabilize over time as the application period extends.