Environmental taxation is an important tool in the hands of member states to combat against climate change and promote environmental sustainability. This chapter describes in detail the taxes that are part of the Portuguese tax system and that have the social function of protecting the environment. For this purpose, a background of the Portuguese Green Tax Reform is provided and each of the environmental taxes considered to be the main burdens of the Portuguese tax system are explained. This study aims to contribute to providing academics and practitioners with more information on environmental taxation and to motivate regulators to develop more articulated green taxation strategies in the future.