Oxygen permeability, electrical conductivity, and thermal expansion of BaBi1-xLaxO3-delta (x = 0, 0.2, and 0.4) perovskite-like solid solutions have been found to decrease with lanthanum content. Thermal expansion coefficients of the ceramics are (11.9-12.8) x 10(-6) K-1. Oxygen transport through the BaBi(La)O3-delta dense ceramic membranes within the membrane thickness range of 0.6 < d < 1.2 mm has been shown to be limited by both bulk ionic conductivity and surface exchange rate.