The wheat straw was treated with different volumes of neem (Azadirachta indica) seed kernel cake water extract (NSKCWE) for up to three weeks at ambient temperature in sealed polythene bags. There was a gradual increase in crude protein content with the increasing volume of extract in the premix and also with the increasing time of fermentation, in comparison to that of the control. The in vitro degradation study indicated that the total volatile fatty acids (TVFA) and in vitro dry matter digestibility (IVDMD) increased with the increasing volume of NSKCWE in the premix but decreased with the increase in the treatment period. The results showed that treatment of wheat straw with NSKCWE for the shortest time period (0 days) was the best among all the treatments.