Due to the good specific strength and the moderate corrosion rate Mg-RE alloys have found growing interest for medical applications as implant material. In this study extruded Mg10Gd has been investigated, once by potentiodynamic method and again under cyclic load. Corrosion exposure is known to reduce the fatigue strength strongly. The data are compared to Mg10Gd ascast condition and show an increase in fatigue properties and similar corrosion behavior. The form of corrosion and the influence of the temperature during voltammetric tests are discussed. A temperature increase from room to body temperature accelerates the corrosion processes. Due to stress peaks under load pitting corrosion is not preferred. The influence of the microstructure on the corrosion form is discussed. Casted Mg10Gd reveals large dendrites, which change into a globular microstructure during extrusion resulting in improved mechanical properties, mostly the elongation to fracture up to 20%.