R–Fe–B/Mn films with different structures have been prepared by DC magnetron sputtering on Si (100) substrates heated at 650 °C. The influence of Mn layer on the magnetic properties of R–Fe–B film is investigated. Addition of Mn layer enhances both the coercivity and the remanence ratio of the R–Fe–B/Mn films. The improvement in the magnetic properties becomes obvious in [Pr–Fe–B(600 nm)Mo(2 nm)Mn(20 nm)] film when a 2 nm Mo as spacer layer is added, the highest coercivity H c of about 18.7 kOe is achieved in the [Pr–Fe–B(600 nm)Cu(2 nm)Mn(20 nm)] film when a 2 nm Cu as spacer layer is added. The coercivity of [Pr–Fe–B( x nm)Cu(2 nm)Mn(20 nm)Cu(2 nm)] n films decreases with increasing the period number of Mn layer for the same thickness of magnetic layer.