The bioelectrochemical system provides a biological pathway to harness energy through electroactive microorganisms, and BES biohydrogen production appears very promising. This review article aims to provide a comprehensive analysis of the current scientific literature on biohydrogen production using BES systems, focusing on mechanisms, types, and related issues. The principles underlying the design and construction of BES, including their components and electron transfer processes mediated by electroactive microbes, are reviewed. Microbial fuel cells, microbial electrolysis cells, and their associated bioelectrochemical systems are examined in terms of their effectiveness and the range of operational parameters. The interaction and coordination between the oligotrophic heterotrophic bacteria and hydrogen producers from complex substrates in biohydrogen production are highlighted, especially exoelectrogenic bacteria and their hydrogen production potential. Various biochemical pathways of hydrogen production and their influencing environment are studied, too. This chapter also emphasises the design and optimisation of various BESs, focusing on how those could enhance the cell’s performance. Scalability, economics, and sustainability are discussed alongside the challenges, innovations, and future possibilities that the scope presents. By collating data from existing literature and knowledge, the article provides insights into future research directions that can help propel the development of biohydrogen production technology applications.