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La (12x) NiO (32d) perovskites present high metallic conductivity and Pauli-paramagnetism, and could be used as electrodes in electrochemical devices such as SOFCs, PEMFCs and MCFCs. Additionally, due to its s* conducting band, this material shows a very high electrocatalytic activity, particularly in oxygen reduction processes, with an ef®ciency comparable to that of platinum. This work describes the combustion synthesis of La (12x) NiO (32d) perovskite powders (x~0 and 0.1) from mixtures of La(NO 3 ) 3 ?6H 2 O and Ni(NO 3 ) 2 ?6H 2 O as cation precursors, and urea as fuel. The as-prepared combustion product, characterized by XRD, DTA/TG, SEM/TEM, BET and dilatometry (after compaction), shows a much higher speci®c surface area than powders obtained via alternative routes and contains La 2 NiO 4 with a typical K 2 NiF 4 -type structure, together with small amounts of NiO. The usual subsequent heat treatments for 1 to 12 h at successively higher temperatures showed that full conversion to La (12x) NiO (32d) can be readily achieved in air at 750 ³C and that the perovskite, after the 12 h heat treatment, remains stable up to 1100 ³C. These results show that the combustion technique is a better and much simpler route to the synthesis of perovskite powders.