Reactive powder concrete (RPC) is oneof the greatest breakthroughs in concretetechnology, as it enables the manufacturingof thinner structures withoutpassive reinforcement. That reduces theload in buildings and increases durability,especially in aggressive environments.The use of metallic microfibersis what provides the increase in tensilestress and the resulting elimination ofreinforcements. However, it is also themost expensive material as well as themost difficult to obtain, which requiresits maximum optimization. Therefore,the aim of this study was to comparethe mechanical properties of the RPCwith three amounts of metallic fibers,1%, 3%, and 5% in volume in relationto the material total, after having determinedthe best curing temperature andeffectiveness of the confining pressurein the fresh state. The mechanical propertiesstudied were the axial compressivestrength, flexural strength, tensilestrength by splitting tensile test, andcapillary absorption. The results showedthat the fibers have little influence oncompressive strength, since there wasonly a small increase as the amountof fibers was increased. However, fortensile strengths, either flexural or bysplitting tensile test, the incorporationof microfibers allowed a significant improvement,obtaining gains of 392%for the flexural strength for the 5%,reaching 59MPa, in comparison withthe 0%, which was 12MPa. There wasalso a decrease in capillary absorption.Keywords: Reactive Powder Concrete (RPC); Metallic Microfibers; Mechanicalproperties, Construction Materials.