Mushrooms can be defined as fruiting bodies of fungi. They have no chlorophyll and therefore lack the ability to synthesize their own food.They get nutrients from supplements like wheat or rice bran. Oyster mushrooms cultivation produces organically grown health food. Oyster mushrooms cultivation is the most economical way to utilize agricultural by products which would otherwise be burned or left to rot in the field polluting the environment. The spent mushroom cultivation media can be used as compost or livestock feed. Therefore mushroom cultivation is a good environmental conservation method.Oyster mushrooms cultivation which is common in Kenya is inexpensive and has a readily available market. Oyster mushrooms cultivation can be done using readily available inexpensive substrates which include straw, sugarcane baggase, coffee residues, straw, banana waste, cotton seed hulls and sawdust. Oyster mushrooms cultivation requirements are Spawns, Substrate, and a room, Supplements like wheat or rise bran, Agricultural lime, Poly bags, string and Water.