Nowadays, oyster mushroom cultivation has become increasing in the developing countries like Ethiopia. But the yield is lower which is due to the substrate performance, availability and cost difference of Substrates materials. This book extremely sorts out the main causes of the problem and its solutions. Hence this book extremely sorts out the performance of different substrates for successful mushroom cultivation. The study reveals the performance of different organic substrates on yield and quality of oyster mushroom (Pleurotus ostreatus).The study also specifically reveals the different substrates effect on yield, efficiency of production, crude protein, crude fiber, and total ash content of oyster mushroom