Abstract: Fire is an important driver in boreal forest ecosystems, and deeply affects biogeochemical processes. The early succession after fire (<15 years) is a critical period influencing recovery of postfire vegetation structure and functions that are impacted by changes of soil nutrients after fire. In this study, we investigated the dynamic characteristics of forest soil phosphorus (P) in an unburned control and burned sites dating 1-year-post-fire, 5-year-post-fire and 11-year-post-fire, respectively  at Huzhong Natural Reserve in the Great Xing’an Mountains of Northeastern China. Our results showed that wildfire immediately caused great increases of soil total P (TP) and available P supply rates, with increasing 55% and 270% respectively, compared to control plots. Such increases had significant positive relationships with fire severity. In the 5-year and 11-year post-fire plots, soil TP concentrations were still higher than those in the control plots. However, we did not find the significant relationship between soil TP and fire severity. In the 11-year-post-fire plots, soil available P supply rates recovered to pre-fire levels. Soil TP and available P supply rates were significantly positively correlated to soil water content. This study indicated that soil P increased immediately after fire and then gradually decreased with time extension of last fire. Fire severity can exert important effects on soil P in the short term, but soil property may become a critical factor influencing soil P with succession.