Fe and Fe-based alloys are great candidates for biodegradable metal implants. In order to achieve high density pure Fe and Fe-35Mn structures, the correct implementation of process strategies and parameters needs to be studied to achieve high density parts. In this study, pure Fe and Fe-35Mn were successfully processed via SLM with a relative density over 99.5%. The lower melting temperature of Fe-35Mn introduced porosity, resulting in a lower processability compared to the pure Fe. In terms of process optimization, most of the typical quality indicators (roughness, density and apparent density) could be correlated to the energy density