The spontaneous surface segregation of ZrC grains from dilute solid solutions (ZrC)1-x(NbC) x with (1-x)0.02 is revealed for the first time. It is shown that the ZrC recipitation is associated with the decomposition of the homogeneous carbide solid solutions (ZrC)1-x(NbC)x. The experimental and theoretical estimates obtained for the segregation energy of ZrC are equal to -50 and -31kJ/mol-1, respectively.