The study was conducted to determine the effect of chemical (NaOH) treatment on dry matter (DM), crude protein (CP) degradation characteristics, and effective degradability of groundnut cake (GNC). GNC was either soaked in 0.5N NaOH or sprayed with it. The 0.5N NaOH treated cake was either air dried or oven dried at 100Cº. Nylon bags technique was employed using three castrated calves. All treatments significantly (P < 0.05) decreased insitu dry matter and crude protein degradation rate as well as the effective degradability of (GNC). The different treatments had the same CP degradation rate at 0, 6 hrs.Both GNC air dried, or oven dried showed lower CP degradation rate than the GNC sprayed at incubation hours 36, 48 and 72 hours. There were no differences in rumen degradation characteristics of CP among the treatments with the respect to the soluble fraction (a), while the NaOH sprayed GNC showed the highest value for the insoluble degradable fraction (b).