Soil contaminants such as heavy metals, organic compounds, microbial pathogens, nanocomposites from various sources are interact with plant system. The translocation, absorption, adsorption, photodegradation, and phytoremediation plays important role in soil–plant interaction of these contaminants. In the current chapter, we have highlighted different soil contaminants their sources and various phenomena takes place through plant-soil system. Nanocomposites are emerging contaminants so special focus has been given to these contaminants. The main causes of soil contamination are discussed in this chapter, along with information on the different pollutants linked to each of them. In the present chapter, types and characteristics of major soil contaminants are elaborated with respect to their origin along with the characteristics of soil that governs the dynamics of the contaminants through plants within the ecosystem.