While the use of various electrical and electronic devices, household chemistry some measuring devices and others in everyday life grows, and their service life is reduced, their share in the structure of municipal solid waste (MSW) continues to increase. These devices and chemicals named household hazardous waste (HHW) contain toxic substances and may cause negative impacts on the environment in the collection and processing of mixed MSW. The tasks of this study are to evaluate the degree of the impact of HHW, contained in the solid waste on the environment; to analyze the modern technologies of MSW treatment taking into account the presence of toxic substances; to make a review of modern technologies of separate HHW treatment and recycling. The study presents the estimation of hazard class modern MSW morphological composition (according to literature sources) by calculation method, taking into account the presence of HHW. Analysis of publications considering the impacts of HHWin MSW on the environment in the most common methods of MSW handling is performed. An overview of technologies in HHW treatment and recycling is presented. The results of the study show that the presence of HHW in MSW may increase the hazard class of the total waste mass and thus the improvement of currently used technologies is required (burial, incineration, composting). On the other hand, the development of separate collection of HHW and the introduction of effective technologies of their treatment and recycling is an integral part of themodern system of MSW treatment.