Compounds formed in the ternary system, MnO-Eu2O3-ZrO2, have been prepared from starting mixtures with a formula, Eu2MnxZr(2-x)O7-delta, by firing at 1623 K in a reducing atmosphere. Those compounds are solid solutions of a pyrochlore type and a rare earth type. The former occurs in the region of x being less than 0.65 and the latter appears in the region x being larger than 0.7. Solubility of manganese ions in those solid solutions has been measured by EPMA and the maximum value reaches about 1.8%. Magnetic properties of the solid solutions indicate that little amount of manganese ions is incorporated in the solid solutions.