Two field experiments were conducted at the New Valley Agriculture Research Station, ARC, during the two successive seasons; 2006 and 2007 to study the effect of varying rates and timing of K and farmyard manure (FYM) applications on forage yield and quality of cow pea local cultivar. The experimental design was arranged in split- split plot with three replications. The study included two time of K application (during and after 21 days from sowing), four K fertilizer rates (0, 50,100, and 150 kg K₂O /fad.) in the form of potassium sulphate and four FYM rates (0, 10, 20 and 30 m³/fad.). Results indicated significant differences between treatments. The results showed that application of 150 kg K₂O/fad. with 30 m³ FYM mixture when K was adding during sowing caused significant increases in the total fresh and dry forage yields as compared with application of 150 kg K₂O/fad. with 30 m³ FYM mixture when K was adding after 21 days from sowing. These increases amounted 37.40, 36.38 and 39.35, 33.08 %, respectively. Meanwhile the same treatment caused significant increases in the total crude protein yield, K, P and Ca uptake. These increases amounted 51.56, 46.47, 80.40 and 39.07 %, respectively.