Sputter deposited (Ni80Fe20/Au/Co/Au)10 multilayers, characterized by alternating in-plane and perpendicular anisotropies of the NiFe and Co layers, respectively, and out-of-plane stripe (labyrinth) domain structure in the Co layers, were bombarded by He + -ions (10 keV) through a mask consisting of polystyrene nanospheres with a diameter of 470 nm. The changes of multilayers magnetic properties after ion bombardment are correlated with the used mask structure.