The paper examined the relationship between individual background (sex, age and social class) and the level of awareness, knowledge and practices of solid waste management in PortHarcourt city residents. It defines solid waste management as the process of collecting, storing, treatment and disposal of solid wastes in such a way that they are harmless to humans, plants, animals, the ecology and the environment generally. The objective of this research is to ascertain the relationship between individual background (sex, age and social class) and the level of awareness, knowledge and practices of solid waste management in Port-Harcourt city residents. The research question addressed the extent of relationship between individual background (sex, age and social class) and the level of awareness, knowledge and practices of solid waste management in Port-Harcourt city residents. This research is based on Ajzen (1991) theory of planned behaviour which states that attitude towards behaviour, subjective norm, and perceived behavioural control, has influence in predicting the behavioural intention and actual behaviour of individuals when participatory decisions are voluntary and under an individual control. The research assumes that the background (sex, age and social class) of Port-Harcourt city residents influences their attitude, subjective norm and perceived behavioural control thus determining the behavioural intention/actual behaviour i.e. level of awareness, knowledge and practices of solid waste management. 800 Port-Harcourt city residents were randomly surveyed from the two local government areas of the city (Port-Harcourt city and Obio/Akpor LGAs) using structured questionnaire. Data collected were subjected to percentage, mean, standard deviation, t-test and chi-square statistical analyses. Findings revealed that Port-Harcourt city residents from the sampled zones are aware of solid waste management problems in their environment but possessed poor waste management practices. The study showed that the propensity for solid waste management practices differed by background (sex, social class and age) of residents. Significant relationships were observed between respondents' sex, age and social class and their level of awareness, knowledge and practices of solid waste management. This research therefore recommends among others: sensitization of Port-Harcourt city residents on the dangers of poor solid waste management, provision of near-by solid waste collection points, enactment of waste management laws with stiffer penalties on offenders, establishment of solid waste recycling plants, effective monitoring of waste contractors, provision of more waste evacuation equipment, provision of more solid waste dump sites and effective monitoring of monthly clean-up activities.