In this work, the yields of hydrogen-rich gases via pyrolysis and air-stream gasification processes were investigated at different temperature ranges. In each run, the main components of the gas phase were CO2, CO, H-2, and CH4. The yields of hydrogen from the pyrolysis and the air-stream gasification increase with increasing of temperature. In general, the gasification temperature is higher than that of pyrolysis and the yield of hydrogen from the gasification is higher than that of the pyrolysis. The percent of hydrogen in gaseous products by pyrolysis from the samples of hazelnut shell, tea waste, and spruce wood increased from 36.8 to 43.5%, 41.0 to 53.9%, and 40.0 to 51.5% by volume, respectively, while the final pyrolysis temperature was increased from 700 to 950 K, and the percent of hydrogen in gaseous products by air-steam gasification from the samples of hazelnut shell, tea waste, and spruce wood increased from 43.3 to 56.9%, 41.0 to 53.9%, and 40.0 to 51.5% by volume, respectively, while the final air-gasification temperature was increased from 900 to 1,250 K.