This study aimed to determine the effects of five phosphorus rates (0, 30, 60, 90 and 120 kg ha(-1)) and three harvesting stages (beginning of flowering, full flowering, and seed filling) on forage yield and quality of hairy vetch (Vicia villosa Roth.). Dry matter (DM) yield, N, P, K, Mn, Cu, Fe, Zn, Ca, Mg, acid detergent fibre (ADF) and neutral detergent fibre (NDF) were determined. Phosphorus rates and harvesting stages significantly affected most of the components determined in hairy vetch. Phosphorus applications increased DM yield, N, P, Ca and Mg contents but decreased K, tetany ratio (K: (Ca + Mg)), ADF and NDF and had no effect on Mn, Cu, Fe and Zn. Harvesting at the late stages caused a reduction in forage quality. Contents of N, P, K, Cu, Zn, Mg and tetany ratios decreased with advancing growth while DM yield, Ca, ADF and NDF contents increased.