Background: Hypophosphatemia (HP) is frequent following liver resection, and thought to represent use of phosphate during liver regeneration. We sought to evaluate the association of post-hepatectomy HP with liver insufficiency and recovery. Methods: Liver resections were retrospectively reviewed from 2009 to 2012 at a single institution. We explored the relationship between HP (defined as serum phosphate ≤0.65 mmol/L), occurrence of initial liver insufficiency (ILI) [bilirubin >50 μmol/L, inteational normalized ratio (INR) >1.7 within 72 hours of surgery] and in-hospital recovery of ILI. Secondary outcomes included 30-day post-operative major morbidity (Clavien grade 3 and 4 complications), mortality, and re-admission. Results: Among 402 patients, 223 (55.5％) experienced HP and 64 (15.9％) met our definition of ILI, of which 53 (82.8％) recovered. Length of stay, 30-day post-operative major morbidity, mortality, and re-admission were similar between patients with and without HP. Among patients with ILI, 44 (68.8％) experienced HP. Following ILI, patients with HP recovered more often than those with NP (90.9％ vs. 65.0％; P=0.03). Conclusions: In patients who experience post-hepatectomy ILI, HP is associated with improved recovery, potentially indicating more efficient liver regeneration. Further studies should explore the usefulness of post-hepatectomy HP as an early prognostic factor of recovery from ILI.