The blocking temperature (TB) of the ferromagnetic and antiferromagnetic mixed films has been studied by Monte Carlo method. TB is found in the simulation, which is discussed with the energy of system and the spin configuration. The calculated results indicate that TB may be produced in the antiferromagnetic coupling system with small number of spins. The effect of little external field and the value of x on TB are also considered. It is found that TB increases with decreasing little external field and the value of x.