Abstract The thermal behaviour of two previously described cobalt telluromolybdates: Co4TeMo3O16 and CoTeMoO6 was investigated and the thermal decomposition products of these compounds were determined. Two new compounds: the cobalt orthotellurate Co3TeO6 and the cobalt telluromolybdate Co3Te2MoO10 were synthesized and their X‐ray and thermal characterization given.