A report by the Federal minister of environment, in December 2013, revealed that the uncontrolled use of plastic materials and the indiscriminate disposal present a clear and imminent danger to our environment and Nigerians. Therefore, this study attempt to uncover the effect of plastic wastes in the context of architectural composition of urban slum settlements with a view to improve the quality of the built environment in Jos Metropolis, Plateau State. Its objectives are to examine the characteristics of slum settlements in study area, and identify strategies for solving plastic waste in the context of architectural composition of urban slum settlements. The study area is Anguwan Rogo community in Jos Metopolis, Plateau State, Nigeria. The methodology employed for this study is physical observation, digital photography, case study and the review of related literature. The study revealed plastic wastes generation has indeed presented negative impacts such as environmental pollution and foul smells, large scale flooding, aesthetic defacement of the built environment. The study therefore recommends that sufficient awareness programmes on dangers of plastic in the environment be organized; improvement in proper plastic waste collection, treatment and disposal, among others.