This article focuses on the analysis of the properties of sewage sludge before and after vermicomposting. The aim of the study is to give detailed characteristics of changes in the properties of sewage sludge after vermicomposting. This will help to obtain a more detailed picture of the processes that take place during vermicomposting of sewage sludge, and a more comprehensive assessment of the possibility of using vermicomposts from sewage sludge as fertilizers. In this article, a large number of parameters for vermicomposts derived from this type of waste have been outlined for the first time. According to the data obtained, vermicomposting resulted in an increase of almost all nutrients, acidification of the substrate, and a decrease in basal respiration. Summing up all the data obtained makes is possible to discuss the potential prospects for the use of vermicomposting aimed at valorization of sewage sludge.