Abstract—This paper reports on an investigation on the effects of partial and complete substitution of crushed granite with recycled plastic on the properties of concrete. A concrete mixture of ratio 1:2:4 by mass was used as control. Four additional mixes of concrete were produced using recycled plastic waste to replace 25%, 50%, 75% and 100% of the volume of crushed granite in the control concrete. The compacting factor test was used to assess the workability of the fresh concrete mixes. A 1500 kN Matest compression machine was used to determine the compressive strength of concrete specimens at 7, 14, 21, and 28 days of curing. The density and compressive strength of concrete reduced as the percentage of recycled plastic increased. However, the workabilities of recycled plastic concrete mixtures were not significantly different from the control concrete. Based on results obtained from the study, recycled plastic can partially replace conventional aggregates in the production of both lightweight and structural concrete.