High Strength Concrete (HSC) is an increasingly important material in the construction of large scale infrastructure projects in the upcoming future due to its high resistance against compressive forces. However, it has low resistance against tensile forces experienced during flexure. The implementation of steel rebar within concrete to create Reinforced Concrete (RC) is a common practice in construction due to the tensile strength and ductility of steel as a material. But there remains an issue of brittleness with HSC, which rebar alone is not sufficient in tackling. Over the past decades, several alternative materials have shown promising results in addressing these weaknesses of concrete, one of these materials are synthetic fibers such as polypropylene fibers (PF) that improve several properties in concrete such as tensile strength, flexural strength, ductility, toughness and crack resistance. Several studies have analyzed the effect of polypropylene fiber on the mechanical properties of plain concrete. However, a lack of studies remains regarding its application in reinforced concrete. The purpose of this study is to analyze the effect of addition of macro-polypropylene fiber at volume fraction, (Vf) dosages of 0.5%, 1.0% and 1.5% on the compressive strength of HSC cylinders, flexural strength, deflection and crack resistance in HSC-reinforced beams. The methodology of this study includes the selection and determination of proportions of constituent materials for HSC mix design, the incorporation of fibers at various dosages within the concrete mix to produce High Strength Macro-polypropylene Fiber Reinforced Concrete (HSMPRC) cylinders, which were then tested for compressive strength. Additionally, the design and preparation of HSMPRC beams, which were then tested for flexural strength and finally comparative analysis of results for each fiber dosage. Results showed that the addition of fiber dosage at 1.0% and 1.5% increased compressive strength, with highest increase recorded for the 1.5%. Flexural strength increased for all fiber dosages to different degrees, with a dosage of 1.0% obtaining the highest flexural strength. The study concludes that the addition of macro-polypropylene fiber improves the compressive & flexural strength of reinforced concrete, however its effect on deflection and cracking patterns is not as conclusive. Thus, the addition of macro-polypropylene does aid in improving the mechanical performance of high strength reinforced concrete.