Ground improvement techniques have gained significant interest in the last few decades as an engineering approach to enhancing soils with poor engineering properties. In alignment with the Sustainable Development Goals (SDGs), specifically SDGs 9 and 11, there is an increasing need for modifying conventional ground improvement technologies through sustainable innovations to support infrastructure development among the rapid urbanization occurring in South Africa. One promising innovative approach is the utilization of plastic waste, which presents an eco-friendly alternative through waste minimization to landfills while promoting a circular economy. Despite the measured benefits which have been demonstrated in the past research works based on the use of plastic fibers in the ground, the adoption of plastic fiber as a reinforcement material remains unpopular, especially in South Africa. While several research has been done about the use of plastic waste in ground improvement, there is a notable gap in the literature regarding the effects of plastic fiber inclusion on the compaction characteristics of soils. Therefore, this research investigated the impact of varying plastic fiber content on the maximum dry density (MDD) and optimum moisture content (OMC) of silty sand through laboratory tests using the modified AASHTO compaction method. The findings revealed that the incorporation of plastic fibers resulted in a general reduction in MDD, while the OMC slightly increased at higher fiber contents. Notably, the optimal plastic fiber addition was found to be 0.5%. The promising outcome from this study encourages further exploration in the use of plastic waste in ground improvement to understand the effect of its inclusion on geotechnical engineering properties.