Indonesia, a tropical country with high biodiversity, is home to a vast variety of edible and medicinal mushrooms, many of which have been used for generations by indigenous communities. The conservation of fungal diversity is very important, even though it faces several challenges such as deforestation, climate change, and research activity. Cultivation presents a promising solution to these challenges. While only a fraction of the country’s mushroom species is currently cultivated, there is significant potential for commercial development. For example, the cultivation of species like oyster mushrooms is increasing, driven by high demand for both food and medicinal products. However, there are still obstacles for farmers, including a lack of knowledge in advanced cultivation techniques, limited access to quality seeds, and issues with capital. Cultivation, particularly of wild species, also offers an opportunity to reduce pressure on wild populations and provide a sustainable source of income for local communities. This chapter reveals the basic biology of mushrooms, the biodiversity of wild edible and medicinal mushrooms as well as the mushroom cultivation technology in Indonesia.