The development of solid oxide electrolysis cell (SOEC) for syngas production has achieved considerable attention because SOEC can directly convert carbon dioxide (CO2) to carbon monoxide (CO). The material of electrolyte for SOEC has a significant effect on the cell performance. Y2O3-stabilized ZrO2 (YSZ) and Sr- and Mg-doped LaGaO3 (LSGM) are interesting electrolytes for SOEC due to their high oxide ion conductivity. Therefore, this work aims to simulate and study the SOECs with YSZ-based and LSGM-based electrolytes by H2O/CO2 co-electrolysis for syngas production. The predicted results of both SOEC models were in good agreement with experiment data. The validated models of both SOECs were used to analyze the effect of temperature. The increase of operating temperature can reduce the cell voltage and power consumption of both SOECs. When comparing both SOECs, the cell voltage of YSZ-SOEC is lower than that of LSGM-SOEC in the range of 800-1,000 oC. On the other hand, the performance of LSGM-SOEC is superior to that of YSZ-SOEC at an operating temperature below 800 oC.