The present invention relates to implants made of a biodegradable magnesium alloy. The inventive implant is made in total or in parts of a biodegradable magnesium alloy comprising: Y: 0 - 10.0% by weight Nd: 0 - 4.5% by weight Gd: 0 9.0% by weight Dy: 0 8.0% by weight Ho: 0 19.0% by weight Er: 0 23.0% by weight Lu: 0 25.0% by weight Tm: 0 21.0% by weight Tb: 0 21.0% by weight Zr: 0.1 1.5% by weight Ca: 0 2.0% by weight Zn: 0 1.5% by weight In: 0 12.0% by weight Sc: 0 15.0% by weight incidental impurities up to a total of 0.3% by weight the balance being magnesium and under the condition that a) a total content of Ho, Er, Lu, Tb and Tm is more than 5.5% by weight b) a total content of Y, Nd and Gd is more than 2% by weight and c) a total content of all alloy compounds except magnesium is more than 8.5% by weight.
