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The effects of long-term excessive phosphorus (P) fertilization on the P fraction changes and P loss risk in orchard soils remain unclear. This study aimed to assess the concentrations of and relationships among the soil total P (TP), Olsen-P and P fractions in pomelo orchard (PO) soil during different fertilization periods. The PO soils were in a severe P overapplication state (905.4 kg P₂O₅ ha^-1 yr^-1), with a high P surplus (773.5 kg P₂O₅ ha^-1 yr^-1) and low P use efficiency (PUE, 14.7%). Such long-term excessive fertilizer P input significantly increased the TP, Olsen-P, and P fraction concentrations and significantly reduced the proportions of Org-P and reduction-P (Red-P) in both the surface (0–20 cm) and subsurface (20–40 cm) soils but increased the proportions of easily soluble P (Sol-P), aluminum-P (Al–P) and iron-P (Fe–P) rather than calcium-P (Ca–P). Furthermore, the P fractions exhibited a corresponding …