The invention relates to a sulfo-aluminous clinker with optimal setting time and short term compressive strengths, comprising a mixture of the following phases: —calcium sulfoaluminate, or C4A3$, in amounts higher than 50% by weight of the mixture, —belite, or C25, in amounts between 2 and 23%, —3C25 3C$ CaX2, X being fluorine or chlorine, between 3 and 15% —C11A7CaX2, X being fluorine or chlorine, between 2 and 12%, both fluorine and chlorine being altogether present in the mixture, and phase C5S2$ being absent. The invention also relates to a method for preparing this sulfo-aluminous clinker, and hydraulic binders comprising this clinker.