The solid solution La 1−x Eu x BaFeCuO 5+δ synthesized in air with 0⩽δ⩽0.13 was studied by X-ray diffraction, 57 Fe Mössbauer spectroscopy and susceptibility measurements. Double perovskite with YBaFeCuO 5 -type structure was observed except for x=0 composition which has a cubic cell. Fe and Cu are generally in square pyramidal environments which differ by their distortion: axially compressed for Fe and elongated for Cu. Mössbauer studies showed the existence of pyramidal Fe 3+ , Fe 3+y and octahedral Fe 4+ . Electric field gradient calculations allowed to better understand the origin of the distortion of the two pyramidal iron sites.