Аннотация:Ceramics with post-firing (600 – 900°C) phase composition represented by calcium sulfate anhydrite CaSO4 and sodium calcium sulfates (Na0.8Ca0.1)2SO4 and Na6Ca(SO4)4 was obtained from a powder mixture of sodium sulfate Na2SO4 and calcium sulfate dihydrate CaSO4 ∙ 2H2O with molar ratio CaSO4 ∙ 2H2O/Na2SO4 = 1. The phase composition of the powder mixture after homogenization (in acetone) in a planetary mill included, in addition to the initial salts, hydrated sodium calcium sulfate Na4Ca(SO4)3 ∙ 2H2O. On soaking in water for 5 and 60 min the weight loss of the ceramic sample fired at 700°C was equal to 15 and 75%, respectively. Na2O–CaO–SO3 ceramics in the form of granules or complex structures obtained by means of 3D printing can be used as a removable (soluble or leachable) porogen and (or) a prototype of a porous space with specified architecture to obtain porous polymeric or inorganic materials. Keywords: sodium sulfate, calcium sulfate dihydrate, calcium sulfate anhydrite, sodium calcium sulfate, porogen