Abstract: The magnetic hysteresis loops of Nd₂Fe₁₄B/α-Fe exchange-coupling multilayers are simulated by micromagnetic theory, and the relation between remanence, coercivity, energy products and soft magnetic thickness are studied. The results show that the hysteresis loops is rectangle and the multilayers are in complete exchange-coupling region when the soft magnetic thickness is below the critical point; By the relation between magnetic properties and soft magnetic thickness, The remanence and maximum energy products firstly enhance and decrease later with the increase of the soft magnetic thickness, but the coercivity decreases monotonically.