An object of the present invention is to provide a production system and production method of tetrafluoroethylene using an ionic liquid. To this end, the present invention is the pyrolysis chamber to pyrolyze the carbon (HCFC) in hydro-chloro-fluoro; A pre-processing unit connected to the thermal decomposition chamber; It is connected to the pre-processing unit, the absorber using an ionic liquid for separating the carbon to hydro-chloro-fluoro; Is connected with the enrichment section of the separation membrane module, low-boiling distillation column for separating the low boiling substance in the upper portion of the tower; Is connected to the lower portion of the low-boiling column, ethylene tetrafluoroethylene column for separating tetrafluoroethylene to the top of the tower; And it is connected to the lower portion of the distillation column in the ethylene tetrafluoroethylene, a primary high-boiling distillation column to separate the high boiling point material to the top of the tower; Tetrafluoroethylene using a separation membrane comprising a provides a process for the production of ethylene system. According to the present invention in a process for the preparation of tetrafluoroethylene, pyrolysis and after performing a pre-processing primary separating the carbon unreacted hydro chlorofluorocarbons through the membrane module to naemeurosseo separate the carbon unreacted hydro chlorofluorocarbons and If recycle improves the process efficiency of the phase separation. In addition, it can be azeotropically distilled in a conventional separation process tower, MeOH absorber, stripper MeOH, MeOH catching tower, can be omitted, such as HFP purifying column, so step size is reduced to 50% or less improves the process economics.