The invention relates to a radio-opaque marker for medical implants. Said marker contains between 10 and 90 weight percent of a biodegradable base component, between 10 and 90 weight percent of one or more radio-opaque elements from the group containing I, Au, Ta, Y, Nb, Mo, Ru, Rh, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Re, Os, Ir and Bi as a marker component and 10 weight percent oF residual components, the aforementioned components amounting to 100 weight percent.