In this study, the nutritive values of treated Walnut hull by Neurospora sitophila were evaluated. The chemical composition of samples was evaluated by laboratory analysis.In vitrodigestibility experiment was done to determine digestibility coefficients of dry matter, organic matter and also digestible organic matter in dry matter (DOMD) to estimate the metabolizable energy (ME) content oftreated Walnut hull. In addition, organic matter (OM) and neutral detergent fiber (NDF) disappearance of samples were determined by In-Situ method at 0, 3, 6, 12, 24, 48 and 72 h after incubation and their kinetics were described using the equation P= a + b(1−e−ct). The nutritive value index (NIV) of samples was calculated using the equation: NIV= a + 0.4b + 200c. The collected data was analyzed in a completely randomized design. The content of tannin and phenol in walnut hull decreased significantly by processing (P<0.05). No significant effect was seen on degradability parameters and nutritive value index. Digestibility coefficient of dry matter, organic matter, digestible organic matter in dry matter and metabolizable energy of treated walnut hull were significantly (P<0.05) lower than untreated Walnut hull. پرونده مقاله