This study investigated the use of social media towards advancing environmental advocacy campaigns in Nigeria. The objectives of the study were to: find out the current use of social media in environmental advocacy campaigns in Nigeria; analyse the effectiveness of utilising social media as a means of raising environmental concern awareness in Nigeria; and understand the determining factors of successful use of social media-based environmental advocacy campaigns in Nigeria. The study employed the Social Cognitive Theory (SCT) and Diffusion of Innovations Theory (DOI) to give the study a theoretical base. The study employed qualitative phenomenological approach where 30 of the respondents were subjected to in-depth interview, such as environmentalists, social media influencers as well as content analysis of social media posts from select advocacy groups. Findings of the study indicated the widespread utilisation of social media among environmental advocacy groups, highlighting social media awareness and mobilisation of the public, as well as the identification of engaging content and social media literacy as necessary conditions for success. The study, by way of conclusion, reaffirmed that, despite certain setbacks associated with misinformation, social media is a priceless resource for environmental activism in Nigeria. The researchers, however, recommended that environmentalists need to prioritise the creation of effective social media campaigns with engaging content coupled with community engagement to achieve maximum effectiveness.