Solution plasma is a non-equilibrium plasma in liquid phase. The reaction field of solution plasma is novel and useful for a wide variety of material science and engineering applications. Active species such as radicals, electrons and ions are generated in the plasma. These active species react with chemicals in liquid at the interface between plasma (gas) and liquid and cause unique chemical reactions owing to variation of liquids, electrodes, as well as operational conditions. Until now, solution plasma process has been applied into the following applications; (1) nanoparticle synthesis, (2) surface modification of nanocarbon, (3) rapid synthesis of nanochannel carbon materials, (4) nanoparticle supported on nanocarbon, and (5) heteroatom-containing carbon substances synthesized from monomers.