This paper investigated the thermal performance analysis of solar thermochemical reactor for syngas production. P1 radiation model was used to analyze the reactor thermal performance. It was found that the temperature distribution resulted in the incident radiation intensity distribution throughout the reactor inner cavity. However, the higher temperature was attributed to a great absorption of incident radiation heat flux intensity. A significant drop in the temperature was observed around the aperture region and sharply decreased with an increase in the incident radiation intensity from the reactor inlet. The reactor initially heating region was increased with an increase in the reactor operating temperature from 1000 K to 1600 K. It was observed that more the heat flux was applied to the reactor, more the reactor was heating up. The instantaneous temperature distribution inside the reactor showed the rise in the temperature was caused by the effect of radiation heat transfer. The carrier gas flow inlet velocity and the drop in the operating pressure have greatly affected the reactor thermal performance. High and more uniform temperature distribution inside the reactor was obtained by better controlling of the reactor operating conditions. (C) 2017 Elsevier Ltd. All rights reserved.