Magnetic properties of EuNixMn1-xO3 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 F-7 Eu3+ 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 Mn3+-Mn4+ 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. (C) 2009 Elsevier B.V. All rights reserved.