Corrosion behaviour and properties of ready parts produced by powder metallurgy depend on their porosity, especially its volume, spread, type (open or closed) and size. Porosity is inversely proportional to sintered material density, and depends on the size and shape of particles, as well as applied compaction pressure (among others). Furthermore, the particle size influences the sintering process itself in addition to the properties of ready-made parts. The results presented here concern the influence of powder shape and size as well as compacting pressure on the porosity, density, surface roughness and corrosion resistance of sintered 316L stainless steel parts. In addition, the effects occurring during the sintering process were analysed. It was observed that the size and shape of particles significantly affect the sintering process. Most importantly, it was observed that applied compaction pressure is the largest factor on the final properties of the samples.