Summary: Analyzing the model of the flexible job-shop scheduling problem (FJSP), an immune genetic algorithm (IGA) is proposed to solve the problem. This algorithm preserves the random global search ability of simple genetic algorithms (SGA), and introduces the immune mechanism by which the necessary vaccine may be extracted with the scheduling vaccinated so as to improve efficiently SGA’s low ability for global search because of immature convergence and low local search ability. Thus, the IGA proposed can provide such ability and convergence rate that will implement the global optimum solution. Experimental results show that the IGA can solve the FJSP effectively.