The present invention relates to a method for preparation of an environmentally-friendly ecological brick from corncob, the method is as follows: even mixing of a corncob culture raw material, high-temperature sterilization of the corncob culture raw material, inoculation of the corncob culture raw material with a specific fungal species, package of the inoculated culture raw material into a mold for culture for a plurality of days in sterile environment, and drying dehydration processing to obtain the environmentally-friendly ecological brick. The environmentally-friendly ecological brick is prepared from the corn cob, rice husk, bran and other agriculture byproducts as raw materials by use of natural growth of fungal hyphae, mycelium kinking forming and other characteristics by the method, the environmentally-friendly ecological brick has the advantages of being simple in process, low in energy consumption, low in cost, environmentally-friendly, ecological, light in weight and good in strength, and the environmentally-friendly ecological brick is used in interior wall decoration in offices and entertainment buildings, can replace some or all of bricks prepared from asbestos separators and other raw materials, and is a new building material with high market value.