This book chapter explores the bioenergy potential of mangrove microbiomes, focusing on their role in sustainable energy production and environmental conservation. It examines various microbial processes within mangrove ecosystems, such as methane production, cellulose degradation, and hydrogenesis, elucidating the metabolic pathways and environmental factors influencing these processes. Additionally, the chapter discusses biotechnological approaches for harnessing mangrove microbiomes for bioenergy applications, including metagenomic analyses, microbial isolation, and bioprospecting. Case studies and applications demonstrate the practical implications of utilizing mangrove microbial resources for sustainable energy generation. Challenges and future directions in bioenergy research within mangrove ecosystems are discussed, along with the integration of nature-based solutions and socio-ecological approaches for promoting sustainable development. Overall, this chapter highlights the significance of mangrove microbiomes in bioenergy research and their potential contributions to environmental conservation and sustainable development.