YBaCo4-x,FexO7 (0.0 <= x <= 0.8) samples were prepared by the solid-state reaction method and the effect of Fe substitution and oxygen adsorption/desorption on the electronic transport properties was investigated from room temperature to 900 degrees C. Fe for Co substitution results in a slight decline in the oxygen storage capacity at lower temperature (200-400 degrees C) and an increase of the phase-decomposition temperature at higher temperature (700-900 degrees C). Both the hole concentration and mobility are reduced in the Fe-containing compositions. Electrical resistivity, Seebeck coefficient, and conduction activation energy increase with the increasing Fe content. A close correlativity between oxygen adsorption and electronic transport behavior was observed in YBaCo4-xFexO7 system. Oxygen adsorption decreases the electrical resistivity and Seebeck coefficients because of the increase of hole concentration at lower temperature and the phase decomposition at higher temperature. (C) 2014 Elsevier Ltd. All rights reserved.