Nickel pyrochlore with the composition Bi₂NiTa₂O₉ (sp. gr. Fd-3m, a = 10.5238 Å) was synthesized by the solid-phase reaction method. The phase formation process for nickel-containing bismuth tantalate Bi₂NiTa₂O₉ with pyrochlore structure was investigated. The synthesis reaction for the pyrochlore phase is described by the interaction of orthorhombic bismuth orthotantalate and nickel oxide. Synthesis proceeds mainly at temperatures above 900°C. The samples are characterized by a porous dendritic microstructure with grain size 0.5 – 1.0 μm. The calcination temperature did not significantly affect the microstructure of the samples. The calcination time of the preparations effects coalescence of grains with the formation of larger particles. The optimal conditions for obtaining pure pyrochlore are: temperature 1050°C and calcination time 15 h.