The global climate crisis has intensified the need for eco-friendly and sustainable fuels. Renewable energy usage has risen by 17% over the last decade, favored for its cost-effectiveness and sustainability. Non-renewable resources are finite, and their extraction is complex, whereas hydrogen (H2) is a promising fuel due to its high energy content (143 GJ/ton) and clean combustion, producing only water without carbon emissions. Hydrogen’s energy output is 2.75 times greater than that of hydrocarbons. It can be sustainably derived from biomass, addressing the energy crisis. Currently, 8% of hydrogen is produced chemically from natural resources, but these methods are energy-intensive and environmentally unsustainable. In contrast, biological hydrogen production, or biohydrogen (BioH2), is more energy-efficient and sustainable. The fermentation process, carried out by microorganisms, is the most suitable process for BioH2 production. This chapter will explore recent advancements in technologies related to microorganisms in biohydrogen production, including genetic engineering methods, nanotechnology methods, and machine learning applications focusing on novel approaches to improve process yields.