Methanol is one of the most consumed chemicals worldwide and its demand is constantly increasing due to the key role that possesses in the transport sector as an environmentally benign fuel. The processes for the production of methanol are divided into two categories: the chemical and biochemical processes. Currently, the chemical processes are those that are used at industrial scale, while biochemical processes are still at experimental stage. Specifically, the dominant chemical processes for methanol production are the natural gas to methanol and the coal to methanol processes. However, these processes are not sustainable, as they use fossil fuels as feedstock and have high levels of CO2 emissions. As a result, more environmentally friendly processes have been researched. Such processes are the biomass to methanol and CO2 to methanol, which are carbon neutral and have the potential to mitigate CO2 emissions. Furthermore, the biochemical processes of methane to methanol and CO2 to methanol are also remarkable, as they utilize microorganisms and enzymes as catalysts under mild conditions. In this book chapter, the aforementioned methanol production processes are thoroughly discussed.