PURPOSE: To prepare fumigated powder of corbicula useful for recovery of vitality and restoration of energy, by fumigating corbicula with keeping an active ingredient contained in it as much as possible, drying and powdering it.

CONSTITUTION: Living bodies of corbicula are collected, put in water so that they vomit soil and sand, fed to a steam or an electric oven, steamed or fumigated, liquid in the corbicula released during the operation is stored separately and preserved, the content of the corbicula with its shell opened is taken out, the content is washed and the soil and sand are removed. The content of the corbicula is fed to a dryer and dried not to be burned, soaked in the liquid preserved separately so that the liquid is wholly absorbed by the content, and the content of the corbicula is dried and fed to a mill into fine powder.