The invention discloses a zero clearance floating regulating device with a variable nozzle, comprising a turbine shell and a nozzle blade, wherein, the turbine shell is provided with a groove matching with the turbine shell and a floating ring is arranged in the groove matching with the turbine shell. The floating ring can move axially by utilizing the pressure difference which is caused by the changes of the before and after airflow speeds of the nozzle blade in the rotating process of the nozzle blade; the floating ring can move from left to right by utilizing the pressure difference which is generated at two sides of the floating ring in the rotating process of the nozzle blade and by adding a floating ring structure on the turbine shell, thus realizing the regulating efficiency of the nozzle blade under low flow rate working condition of the motor. Compared with traditional transmission structure with fixed clearance, the regulating efficiency of low-speed gas can be improved by 5% or more; the invention has the advantages of simple structure, easy realization, obvious effects, thus effectively solving the problem of efficiency loss of a vane-type variable area supercharger in air flow regulating process.