Slovenia with its diverse environment is home to more than 2400 fungal species out of which especially many macromycetes have for millennia been used worldwide as natural remedies. These species of mushrooms were in the past picked from the nature, but today can be cultivated as fruiting bodies or fungal biomass on different substrates. They possess immunomodulating, antiviral, antibacterial and anticancer activities and can be used against allergies, dementia, Alzheimer disease and in many other diseases. They represent a vast potential as natural remedies with no or very little adverse effects and can be processed into food supplement or further developed into medicines. These mushrooms are a natural treasure, which enables us to be more self-sufficient if we cultivate them for medical and certain species for nutritional purposes as well.