In this study, a series of laboratory experiments were conducted to investigate the effects of slow pyrolysis parameters of temperature, air mass flow rate, heating rate, and residence time on cud and waste paper char yields. Cud and waste paper were heated with a slow pyrolysis temperature (167 0 C) to produce the biochar. The degree of decomposition depends on the feedstock used and process conditions. As the results revealed that the biochar yield, depends mainly on the applied controlled temperature and airflow rate. During the experiment, the primary airflow rate makes the process more slowly pyrolysis. Both primary and secondary air inlet opening at the same time provides high temperature and less biochar yield. The experiment was conducted under a slow pyrolysis temperature of 167 0 C, moisture 15%, and air mass flow rate of (0.35 - 1.5kg/s). At this temperature; 30kg of feedstock, cup, and paper in the reactor produces 10kg- 23kg and 10-20kg respectively of biochar yield at the same airflow rate of 0.35m/s. Temperature gradient appears and tends to increase as the airflow rate increases within the limited values. But the biochar yield reduces as the pyrolysis temperature and airflow rate increase.