In order to solve excessive accumulation of phosphorus in the soil of intensive facilities, this study conducted a pot experiment to explore different types of soil conditioners on dry matter accumulation, phosphorus uptake and changes in soil phosphorus forms of waxy maize. The results showed that maize grew best under biochar 70% + alum 30% treatment with the highest dry biomass of 44.6 g/plant, increased significantly by 19.57% than control treatment. The application of conditioner decreased the contents of total phosphorus and water-soluble phosphorus to varying degrees. In terms of changes in soil inorganic phosphorus composition, 100% alum and 100% biochar treatments increased the content of slow-acting phosphorus sources, and 70% biochar + 30% alum treatment significantly increased the content of fast-acting phosphorus sources. Biochar 70% + alum 30%, biochar 30% + humic acid 30% + alum 30% treatments effectively inhibited the activity of soil alkaline phosphatase and the mineralization of soil organophosphorus. On the whole, biochar 70% + alum 30% treatment has good comprehensive performance in releasing soil potential phosphorus sources, improving soil available phosphorus sources, promoting crop phosphorus absorption, and improving crop dry matter quality accumulation.