Micro‐powder injection moulding (μPIM) is a promising mass manufacturing technique for the microsystem technology. Because typical applications – like sensors or actuators – need to withstand serious mechanical loadings, the investigations of the mechanical properties are of vital importance. Therefore, we implemented a small‐scale testing setup that enables tensile and tension–tension–fatigue testing of freestanding micro‐samples. This allowed for investigating tensile and fatigue properties of conventionally produced and μPIM 17‐4PH stainless‐steel thin membranes. The conventionally produced samples were machined from bulk material and showed properties and lifetimes comparable with the best bulk samples. The μPIM samples showed a weaker but more ductile behaviour, due to a ferritic phase and SiO2 inclusions. But their ultimate tensile strength of up to SU = 1021 ± 48 MPa and their relative fatigue strength of ≈46% SU (R = −1) are still comparable with average bulk values. This indicates the high potential of μPIM materials.