Abstract: This study review focused on indicating wastewater treatment technologies used in Kenya and determine the most feasible and effective treatment method that can be applied in slum areas. This systematic literature review showed that the most commonly used treatment method in Kenya is the use of single or combined constructed wetland, stabilization ponds coupled with constructed wetland, stabilization pond with aerated lagoons, and also conventional wastewater treatment systems. However, the conventional method is costly and requires high implementation, maintenance and operation. Yet, most of the final effluents of the treatment system do not meet the National Environmental Management Authority (NEMA) standards hence posing a threat to the environment and human life. Found that most of the wastewater treatment plants were not effective in removing the nutrients (phosphorus and nitrogen) to the required standards.