The nanocomposite electrode is a promising technology to improve the electrochemical performance of intermediate/low temperature solid oxide fuel cells (SOFCs). Within the nanocomposite electrode, the space charge layer (SCL) effect is likely to alternate the oxygen vacancy transport adjacent to the three phase boundaries (TPBs), which is one of the key factors to improve the electrochemical performance of the electrodes. Existing studies usually adopt Poisson-Boltzmann (PB) equation to predict the SCL effect, in which all the charge carriers are assumed to be in the electrochemical equilibrium state and the net current of the conductor is nearly zero. Apparently, the PB equation is incapable of predicting the SCL effects under typical SOFC operating conditions, since the net current is obviously not zero. In this paper, based on the patterned electrode, we develop a numerical method via coupling the Poisson equation with the mass conservation equation of charge carriers for the oxygen vacancy transport with considering the SCL effect under SOFC operating conditions. Our results show that an obvious gradient is observed in the oxygen vacancy concentration near the TPBs due to the SCL effect, which leads to a remarkable diffusion current that is even larger than the migration current driven by the potential gradient. The SCL resistance is computed to quantitatively characterize the influence of the SCL effect on the oxygen vacancy transport. The SCL resistance shows a decreasing tendency with the increasing of the dimensionless Debye length and dimensionless potential, but it increases with the increasing of the dimensionless average current density. These results and the numerical method can be helpful in improving the performance of intermediate/low temperature SOFCs via rationally designing robust nanocomposite electrodes.