Аннотация:Examples of various plasma-chemical processes in heterophase plasma-liquid systems with secondary discharges are presented. The secondary discharges were supported by plasma flow from a coaxial-end discharge or transversal arc and by electrical discharge in a gas channel with liquid wall. The plasma parameters in plasma-liquid systems were studied by optical emission spectrometry, current-voltage measurement and probe technique. The properties of work liquids after the plasma treatment were explored by UV absorption and luminescent spectroscopy. The output solid products with nanoparticles were investigated by scanning optical and atom-force microscopy. The output gas products after the plasma reforming were analysed by mass-spectrometry and gas chromatography technique. The features of plasma-aasisted reforming of hydrocarbons in plasma-liquid systems with secondary discharges are discussed in the work.