A process for preparing mist, which includes micro/nano solids or liquids, and a process for forming new materials by mist gas discharge, and also an apparatus for forming new materials. The advantages are: as compared to common gases, mists exhibit broader selection range of elements and compounds and broader range of suitable temperature and pressure. Due to the presence of mist AI(m), in a sealed container, the concentration of A in unit volume of mist is far higher than the concentration of A in unit volume of gas. Under specific conditions, the physical/chemical reactions can be carried out more easily, and new materials can be formed with higher efficiency.