The influence of scrap plastic drinking bottles on the strength and swelling qualities of lean clay is investigated in this paper. Before use, waste plastic bottles (WPB) were cut into 4 mm strips and mixed with soil in proportions of 1, 2, 3, 4, and 5% (dry weight of soil). The prepared materials were subjected to three standard tests: Proctor test, swelling, and strength penetration test California Bering Ratio (CBR). The results of tests revealed that WPB have a substantial impact on the clay’s compaction, swelling, and strength qualities.