A prefabricated monolithic modular self-supporting sanitizable clean room system comprises at least one clean room having large monolithic panels, consisting of a high density foamed polystyrene inner core, and coated in fiber-glass/polyester, the system having the following particular characteristics: high productivity with increase in product shelf life, absolute air filtering, temperature, humidity and overpressure control, reduced washing and drying times, maximum washability, high efficiency air treatment mixer system with desiccant dehumidification wheel, significant reduction in costs of civil works and also including all the prefabricated utilities.