The sol–gel method has been developed for the preparation of pure Ba(Mg1/3Ta2/3)O3ceramics. This involves the reaction of the heterometallic alkoxide Ta2Mg(OEt)12with hydrated barium hydroxide Ba(OH)2·8H2O. Complete crystallization of the sol–gel‐derived powder is achieved at 600°C, leading to a cubic perovskite type phase. After sintering at 1400°C (2–5 h), a trigonal cell arises from Mg–Ta ordering (the degree of order is greater than 0.9), and about 98.5% of the theoretical density is obtained. Preliminary microwave dielectric measurements show that the dielectric constant and the unloadedQuof the ceramics are 24.2 and 6750, respectively