Concrete has been used as a protective structure to resist impact and blast loads for many years. Recently, researchers have been developing various strengthening methods to increase the impact resistance of concrete. The study includes, first, investigating the basic properties of normal concrete with plastic fibers such as compressive strength and flexural strength, and, secondly, a research of the low-velocity impact resistance of high-performance concrete with steel fiber specimens using a falling mass dropped from the same heights. The impact test used 500×500×60 mm slabs made of plain concrete with different volume fractions of plastic fiber. Test results indicated that incorporating plastic fibers in concrete significantly improves its impact resistance. There is a marginal increase in energy absorption for a change in fiber content from 0.5 to 0.75 %. The authors also considered other parameters besides waste plastic fiber percentages, e.g. degree of interaction (DOI), the method of fixing the stud to a steel plate (welding and epoxy), and the type of structure (composite and non-composite). A theoretical analysis revealed a difference between theoretical and experimental results due to repetitive strikes in the experimental test resulting in accumulated residual deflections.