Magnetic properties of EuNi x Mn 1 − x O 3 were studied in bulk form and, for a specific composition (x=1/3), as epitaxial thin film. Paramagnetic properties are interpreted as a VanVleck contribution of the 7 F Eu 3+ configuration, showing linear decrease of the effective moment and VanVleck susceptibility as x(Ni) increases. The ordered state was studied for three particular compositions which describe different regimes: canted-antiferromagnetism for x(Ni)=1/4 and ferromagnetism for x(Ni)=1/2, the composition x(Ni)=1/3 being at the frontier of both regimes. Nominal composition x(Ni)=1/3 was chosen for epitaxial films, since it corresponds to a critical concentration for which a maximum number of pairs Mn 3+ –Mn 4+ and optimal double-exchange interactions are found. The coercive field is enhanced, and the field dependence of T max is reduced as if the coherent ferromagnetic phase is favoured at the boundary of the magnetic domains.