Metallic magnesium is biodegradable biocompatible and bioactive; this is the reason why porous Mg scaffolds find applications within tissue engineering. Porosity and pore size are crucial morphological properties of a porous scaffold for bone regeneration. Good conditions for bone formation and vascularization can be achieved with a porosity of minimum 40% and a minimum recommended pore size of 100μm. Magnesium scaffolds were produced from Mg starting powders by a powder metallurgical method using ammonium bicarbonate as space holder. The amount of porosity and pore size was controlled varying the size of the space holder. Four different ammonium bicarbonate particle sizes in the range of 10 – 800 µm with a porosity of 40% were studied. The porosity pore morphology and scaffold microstructure was characterized. A protective biocompatible polymeric coating was applied onto Mg scaffolds in order to control degradation.