Nowadays, the global energy crisis has been encouraging the development of renewable energy. Biomass has emerged as one of the most attractive renewable energy sources in Indonesia. Compared with fossil fuels, biomass is available in abundant quantity, renewable, and non-toxic. Pyrolitic, a method to process biomass, was performed in a household cook stove (also known as a pyrolitic stove). The pyrolitic stove will be developed as an option for substituting traditional cook stove improve the thermal efficiency. In this study, the pyrolitic of twigs of Indonesian teak in the pyrolitic stove was investigated. The influence of bottom air apertures on the household pyrolitic stove performance was studied. It was found that the decreasing number of bottom air apertures resulted in a longer leg-phase of temperature change, higher char yield, lower ash yield, and energy recovery. However, the temperature change was only slightly affected by one-third open outer air apertures condition. According to the condition performed in this study, 60 bottom air apertures in the stove provided an optimum energy recovery for cooking.