With the purpose of providing scientific bases for vegetation restoration in rocky mountainous areas, this study investigated the effects of different forest vegetation restoration methods on soil phosphorus content and fractions. Four forest restoration methods—namely pure stands of Acer pictum, mixed stands of Acer pictum - Ligustrum quihoui, pure stands of Pistacia chinensis, and mixed stands of Pistacia chinensis - Pyracantha fortuneana —in Xuzhou's rocky mountainous areas were selected. We measured soil phosphorus content and fractions, soil carbon content, soil nitrogen contensoil, soil microbial biomass, soil alkaline phosphatase activity in the 0—10 cm and 10—20 cm soil layers, as well as the chemical composition characteristics of litter and fine roots in the four forest types. The results indicated that:(1) Compared with pure stands of Acer pictum and pure stands of Pistacia chinensis, the corresponding mixed stands exhibited increased total phosphorus, total inorganic phosphorus, total organic phosphorus, and available phosphorus by 17.5% and 6.6%, 20.1% and 11.2%, 15.3% and 2.9%, 36.3% and 39.5%, respectively. (2) The mixed stands of Acer pictum - Ligustrum quihoui and mixed stands of Pistacia chinensis - Pyracantha fortuneana had 48.7% and 32.8% higher soil labile phosphorus, 18.6% and 11.9% higher medium-activity phosphorus, and 19.0% and 7.3% higher stable-state phosphorus content, respectively, compared with the corresponding pure stands. (3) Redundancy analysis showed that soil total nitrogen content and fine root total phosphorus content were the main factors influencing variations in soil phosphorus content and fractions, explaining 56.9% and 60.6%, 49.3% and 54.0%, respectively. (4) Structural equation modeling revealed that alkaline phosphatase activity and soil organic carbon content had extremely significantly direct positive effects on labile phosphorus (P<0.01), with path coefficients of 0.351 and 0.311, respectively, while soil and litter carbon to nitrogen ratio had significant negative effects (P<0.05), with path coefficients of 0.321 and 0.183, respectively. In summary, at this experimental site, compared to pure stands, the mixed stands increased the quantity and quality of aboveground litter and fine roots, reduced the carbon to nitrogen ratio of litter, and accelerated the organic matter decomposition rate, thereby enhancing phosphorus nutrient recycling and increasing the content of carbon and nitrogen in the soil. This provided abundant nutrients to microorganisms, increased soil alkaline phosphatase activity, and promoted the conversion of soil organic phosphorus to inorganic phosphorus, thus enhancing soil available phosphorus content. Therefore, it is recommended to prioritize the creation of mixed stand of trees and shrubs in future vegetation restoration in rocky mountainous areas.