The homogeneity ranges and crystal structure of solid solutions of Nd1-xBaxCo1-yFeyO3-delta composition were detected. Depending on introduced barium concentration Nd1-xBaxCo1-yFeyO3-delta oxides have been crystallized in the orthorhombically distorted (x = 0.05, sp. gr. Pbnm), cubic (0.6 <= x <= 0.9, sp. gr. Pm-3m) perovskite structure or double perovskite structure NdBaCo2-xFexO5+delta (0.0 <= x <= 1.4, sp. gr. P4/mmm). The dependencies of unit cell parameters versus composition of the Nd1-xBaxCo1-yFeyO3-delta solid solutions were obtained. It is shown that the values of oxygen nonstoichiometry in Nd1-xBaxCo1-yFeyO3-delta, determined by a thermogravimetric method within the temperature range 298-1373 K in air, increased with the raise of barium and cobalt content. Average values of thermal expansion coefficients for the Nd1-xBaxCo1-yFeyO3-delta oxides (0.8 <= x <= 0.9 and 0.7 <= y <= 0.9) visibly increased with temperature from (13.5-14.5) x 10(-6) K-1 at 300-700 K up to (23.2-26.2) x 10(-6) K-1 at 700-1373 K.