Under mild solvothermal conditions two novel thioantimonates(V) [Sm(en)4]SbS4 x 0.5en (1) and [Sm(en)3(H2O)(micro-SbS4)]infinity (2) were synthesized; the structure of 1 contains discrete [Sm(en)4]3+ and [SbS4]3 ions, while 2 consists of neutral [Sm(en)3(H2O) (micro-SbS4)] one-dimensional chains.