The purpose of this study is to find the possibility of using plastic bottles in the hollow concrete blocks. The voids are created at equal diatance in the masonry units using the plastic bottles. For this study 500ml plastic bottles are used around that a concrete is placed to form a masonory units. After casting and curing the compressive strength of the conventional hollow concrete block and concrete block with plastic bottles is tested. The testing results shows about a 40 % increase in compressive strength for the hollow concrete block with plastic bottles for 28 days curing. This proves further research is necessary regarding determine the appropriate mix design and incorporate plastic bottles in hollow space in all other aspects. The results are obtained for the curing period of 7, 14 & 28 days. © 2020 Elsevier B.V., All rights reserved.