There are still some discrepancies about which of tubular and planar solid oxide fuel cell has a advantage for commercial application.For the energy conversion,it is always expected that the process proceed in reversible ways.Through analyzing the irreversible phenomena taking place in the two types of electrochemical energy conversors,the conversion efficiency can be predicted.In this article,non-equilibrium thermodynamic theory was used to analyze the thermodynamic characteristics of both types of SOFC.Under some proper assumptions,the entropy production was calculated for one-dimensional model.The calculation shows the advantage of tubular SOFC vs.planar one.