Hydrogen production using current fueling facilities is essential for near- term applications of fuel cells. A preliminary process for developing natural gas autothermal reforming (ATR) reactor for solid oxide fuel cell (SOFC) was performed in this study. Catalyst scanning was performed for three catalysts and Pt based catalyst selected for further study. Using Pt catalyst we determined feeding conditions for the thermal neutrality by varying O2/CH4 with selected temperatures and feeding conditions. Temperature profiles of a reactor were observed and reformed gas composition was analyzed to evaluate efficiency, conversion and heat of reaction. O2/CH4 showed strong effects on reactor temperature, efficiency and conversion. Thermal neutral conditions were determined for two cases of ATR system on the basis of yields of products of experimental results. These conditions could be used as a guideline for reformer design and operation parameter for self-sustaining ATR.