Background and aims <p>Nitrogen (N) enrichment is often associated with exacerbating phosphorus (P) limitation; however, the adaptive responses of soil P availability and plant P resorption to N enrichment-induced P limitation remain unclear in boreal peatlands.</p> Methods <p>We conducted an eight-year N addition experiment (0, 30, 60, and 120 kg·N hm⁻²·year⁻¹) in a boreal peatland in northeastern China, and measured the variations in leaf P resorption of eight vascular plant species, soil acid phosphatase activity, and soil CaCl₂-, citric acid-, acid phosphatase-, and HCl-extractable P fractions at 0–10&#xa0;cm and 10–20&#xa0;cm depths after N addition.</p> Results <p>Nitrogen addition generally elevated leaf N:P ratio in the eight selected vascular plants but reduced soil total P concentration at both 0–10&#xa0;cm and 10–20&#xa0;cm depths, indicating the intensified P limitation. Despite unchanged soil phosphatase- and HCl-extractable P fractions, N addition generally enhanced soil acid phosphatase activity, and CaCl₂- and citric acid-extractable P fractions. The simultaneous increases in soil acid phosphatase activity and these bioavailable P fractions exhibited that N addition accelerated organic P turnover and subsequently increased&#xa0;P availability. Furthermore, N addition enhanced plant leaf P resorption efficiency and proficiency. The significant relationship between leaf P resorption and mature leaf N:P ratio showed that plants enhanced their internal P cycling to adapt to N addition-induced P limitation.</p> Conclusions <p>Soil P availability and plant internal P cycling increase synergistically to adapt to N enrichment-induced P limitation, which are essential for understanding nutrient cycling and limitation in boreal peatlands.</p>