The compression forces dominate the behavior of columns, which is why they're called compression members. Reactive Powder Concrete (RPC) and steel fibers can provide a new solution to enhance columns' compressive strength capacity and ductility. In this thesis, the effect of concrete mix, ties number, and steel fiber dosage are studied experimentally and theoretically on columns. The columns' dimensions are 500mm x 100mm x 100mm. Experimental investigation and finite element analysis are performed on twelve columns with two types of concrete mixtures, conventional concrete, and RPC. RPC having 3 different dosages of steel fiber depend on cement weight 1%, 2%, and 3%, and different ties numbers. The results of the experimental work and the load-displacement curve illustrate that the RPC column specimens have a higher ultimate load; the increases are between 52% to 152%, ductility has increased between 40% to 133%, and toughness has increased between 146% to 404% above the control concrete columns specimens. The composition between numerical (Finite Element) simulations and experimental records is satisfactory for the reference columns and the RPC column specimens. Both finite element analysis and the experimental results indicate that the appliance of RPC gave the columns a higher level of ductility and could withstand higher loads than the columns with ordinary concrete.