Much effort has been devoted recently to the development of near-net-shaping processes in water, Agarose has been demonstrated to be a suitable gelling agent for aqueous forming. However, its high cost and the difficulties in controlling the rheological properties have restricted large-scale applications. In this work a novel gelling binder, namely carrageenan, is proposed as a low-cost and high-gel-strength additive for gel-forming ceramic powders. The capability to obtain silicon nitride parts by carrageenan gelation is described. Aqueous silicon nitride slips are prepared at pH >11 to a solids content of 70 wt% using tetramethylammonium hydroxide as a dispersant, Dissolution and gelation of carrageenan are studied by continuous measurements of viscosity with temperature for solutions prepared at different pH values. The final injection slips prepared by mixing at <60C the previously heated suspension and the carrageenan solution are theologically characterized also. After the blend is injected into cooled nonporous molds, gelling occurs in a few seconds and samples can be dried in air for 24-48 h, Green densities of 52% of theoretical are obtained.