On the basis of a micromagnetic model, magnetization reversal in two antiferromagnetically coupled ferromagnetic layers (10 nm t1/0.9 nmM/t2 nm films with t2=2, 3, 4, 5 nm, here t1 and t2 are the top and bottom layers, respectively, and M the spacer) with the same random anisotropy arrangement can be represented by a computer simulation. The calculation indicates that the appearance of a full antiferromagnetic coupling at remanence requires the antiferromagnetic coupling constant j=-3.5 erg/cm2 for the 10 nm t1/0.9 nmM/3 nm t2, films and it needs a large j value if t2 increases for the case of Ku2=Ku1=1×106 erg/cm3 and Ms1=Ms2=400 emu/cm3. Hc follows the equation Hc=-0.755j/Mst1 (j≪0). Why the calculated Hc values deviate from Hcmax=-j/Mst1 is discussed. © 2001 American Institute of Physics.