Declining soil quality and insufficient phosphorus supply are important factors that limit the normal growth of garden plants. As phosphorus-rich organic matter，urban sludge can effectively improve soil structure and enhance soil phosphorus supply capacity. However，there is still insufficient research on the improvement effect of urban sludge application on different types of garden soil and its phosphorus components. In this study，the red soil and yellow-brown soil in Wuhan were sampled，and soil culture experiments were carried out by applying 0%，3%，5%，10%，15% of decomposed sludge to explore the effect of sludge addition on soil phosphorus components and phosphatase activity，in order to provide theoretical basis and technical guidance for the efficient utilization of phosphorus resources in sludge and the construction of green and economical gardens. The results showed that after the addition of sludge，the soil pH value changed towards neutral，and as the amount of sludge application increased，the total phosphorus and available phosphorus contents of both soils showed an increasing trend. Adding sludge also had a certain impact on the phosphorus components of red soil and yellow-brown soil. After adding sludge，the phosphorus in both soils was mainly inorganic phosphorus，which mainly increased the contents of NaOH-Pi，NaHCO3-Pi and D.HCl-Pi；The phosphorus form with the greatest increase among organic phosphorus was NaOH-Po，and the NaHCO3-Po content dropped significantly after 60 days of culture. Sludge-adding increased the phosphatase activity in the soil. After 60 days of cultivation，adding 15% sludge had the best effect on improving the acid(alkaline)phosphatase activity of the two soils，among which the acid phosphatase activity of red soil and alkaline phosphatase activity were the best. The activities of the two enzymes in yellow-brown soil increased by 68.6% and 181.8%，respectively，and the activities of the two enzymes in yellow-brown soil increased by 178.7% and 88.9%，respectively. After the application of sewage sludge，the phosphorus availability of garden soil was significantly improved，and the content of various forms of phosphorus and phosphatase activity in the soil increased significantly.