Expansive soils occupy considerable land in many countries across the world. These soils undergo peculiar volume changes upon wetting and drying due to the presence of expanding clay minerals. These volume changes threaten the stability of lightweight structures. Several remedial techniques were developed by various researchers to reduce these damages. Chemical alteration is one of the remedial techniques that involves supplementing the higher valency cations to satisfy the charge deficiency of clay minerals. In the current study, an effort is made to investigate the effects of magnesium chloride on the strength and swelling characteristics of a nearby black cotton soil by using the Atterberg limit test, compaction characteristics, unconfined compressive strength (UCS), California bearing ratio (CBR), and swelling characteristics tests in accordance with Indian standards. According to this investigation, adding magnesium chloride enhanced the maximum dry density while drastically lowering the ideal moisture content. According to the results of the UCS test, BC soil and magnesium chloride had a higher value than untreated BC soil. The increase in UCS for the soil and magnesium chloride mixture is 1.86 times. There is a 2.32 times improvement in the CBR value for the soil and magnesium chloride mixture in comparison to the Untreated BC soil. Results showed that BC soil qualities might be improved with magnesium chloride and that adding 6% of magnesium chloride solution would have a noticeable impact on the admixtures.