E-participation systems have emerged as valuable tools for enhancing democratic processes and citizen engagement in decision-making. These systems leverage information and communication technologies to facilitate interactions between citizens and government entities. While e-participation systems hold great potential, they also face numerous challenges that hinder their effectiveness and adoption. This paper aims to provide a comprehensive study of the challenges encountered by existing e-participation systems, focusing on key areas such as technological, social, legal, and organizational aspects. By understanding these challenges, policymakers, system developers, and stakeholders can devise strategies to overcome them and foster successful e-participation initiatives. This paper conducts a meta-analysis of past studies between 2017 and 2023 on the challenges faced by existing e-participation systems. Through this meta-analysis, the authors find that e-participation systems encounter multifaceted challenges spanning various dimensions, including technological, organizational, political, and social aspects.