We have studied the magnetic properties, microstructure, and mechanical properti es of a high-coercivity FeCrCo alloy. Based on the experiments, the high-coerciv ity can be obtained by selecting suitable composition and heat treatment process . According to the TEM and XRD results, we drew a conclusion that the main eleme nt and the minor metallic dopants control effectively the conformation of phases . Thermomagnetic treatment induces the separation of the ferromagnetic and param agnetic phases, and a spinodal structure forms that results in magnetic-hardenin g. The large composition contrast between the two phases could improve the coer civity of the FeCrCo alloy obviously