The main purpose of this study is to investigate the impacts of green finance, fintech, and environmental innovation on CO2 emissions of the G-20 countries. This study seeks to determine how these variables play a role in the environment and add to the existing literature on these variables. This study investigated the period comprising the years from 1990 to 2021. The purpose statement of the present study is determined and it develops a comprehensive analysis and integration of the current theoretical and empirical literature regarding previous literature. The purpose of this research is to summarize the association among green finance, fintech, financial inclusion, GDP and environmental innovation on CO2 emissions for the G-20 countries. In addition, this research aims to discover the existing literature by examining the theoretical frameworks as well as empirical evidence presented in published articles. Besides, the paper analyses the theoretical approaches that make the theoretical background transparent and show how the principles and mechanisms of the methods are interconnected. This research endeavours to be of great importance to the world of green finance, fintech, financial inclusion, GDP, and environmental innovation by means of undertaking an extensive literature review and synthesis utilizing current theories and studies dealing with the influence of green finance, fintech, financial inclusion, GDP, and environmental innovation on CO2 emissions in G-20 countries.