Nd doped Y 0.8Ca 0.2Ba 2- xNd xCu 3O y YBNCO compounds with x≤0.50 have been prepared by the solid state reaction technique. The structure and the superconductivity for YBNCO compounds are characterized. The zero resistance transition temperature Tc0 for each sample was measured. Tc0 increases with the increase of the content of Nd in YBNCO as x≤0.15, and decreases as x≥0.20. X-ray diffraction studies show that there is no structural phase transition in the whole doping range. The dependencies of the lattice constants and some other structural parameters on the content of Nd for the samples YBNCO with x≤0.20 have different behaviour than that for the samples with x≥0.25. It seems that the superconductivity of YBNCO is related to the structural changes due to Ca and Nd co-doping.