The present invention provides a method for producing tetrafluoropropene represented by formula (1) by bringing monochlorotrifluoropropene represented by formula (2) into contact with anhydrous hydrogen fluoride in the presence of a catalyst, the method being capable of maintaining the conversion of the starting material and the selectivity for the target product within an excellent range, while reducing degradation of the catalyst to maintain the reaction for a long time. The invention specifically relates to a method for producing tetrafluoropropene represented by formula (1) CF.sub.3CXCHX wherein Xs are different from each other and represent H or F, including the step of bringing an organic substance containing monochlorotrifluoropropene represented by formula (2) CF.sub.3CYCHY wherein Ys are different from each other and represent H or Cl into contact with anhydrous hydrogen fluoride in the presence of a catalyst in a reactor, wherein the amount of the anhydrous hydrogen fluoride supplied to the reactor is 30 moles or more per mole of the organic substance supplied to the reactor.

The present invention provides a method that produces a composition containing 1223xd and/or 1213xa by a gas-phase reaction, and that achieves production efficiency higher than known methods. The present invention provides a method for producing a composition containing at least one fluorine-containing olefin selected from 1,2-dichloro-3,3,3-trifluoropropene (HCFO-1223xd) and 1,1,2-trichloro-3,3,3-trifluoropropene (CFO-1213xa), the method comprising subjecting at least one starting compound selected from a chlorine-containing alkane represented by Formula (1-1): CF.sub.3CHXCHX.sub.2, wherein each X is independently H or Cl, with the proviso that at least one X represents Cl, and a chlorine-containing alkene represented by Formula (1-2): CF.sub.3CXCX.sub.2, wherein each X is independently H or Cl, with the proviso that at least one X represents Cl, to a gas-phase oxychlorination reaction in a temperature range of 380 C. or lower in the presence of oxidative gas and hydrogen chloride gas.

The present invention provides a method that produces a composition containing 1223xd and/or 1213xa by a gas-phase reaction, and that achieves production efficiency higher than known methods. The present invention provides a method for producing a composition containing at least one fluorine-containing olefin selected from 1,2-dichloro-3,3,3-trifluoropropene (HCFO-1223xd) and 1,1,2-trichloro-3,3,3-trifluoropropene (CFO-1213xa), the method comprising subjecting at least one starting compound selected from a chlorine-containing alkane represented by Formula (1-1): CF.sub.3CHXCHX.sub.2, wherein each X is independently H or Cl, with the proviso that at least one X represents Cl, and a chlorine-containing alkene represented by Formula (1-2): CF.sub.3CXCX.sub.2, wherein each X is independently H or Cl, with the proviso that at least one X represents Cl, to a gas-phase oxychlorination reaction in a temperature range of 380 C. or lower in the presence of oxidative gas and hydrogen chloride gas.

The present invention provides a method that produces a composition containing 1223xd and/or 1213xa by a gas-phase reaction, and that achieves production efficiency higher than known methods. The present invention provides a method for producing a composition containing at least one fluorine-containing olefin selected from 1,2-dichloro-3,3,3-trifluoropropene (HCFO-1223xd) and 1,1,2-trichloro-3,3,3-trifluoropropene (CFO-1213xa), the method comprising subjecting at least one starting compound selected from a chlorine-containing alkane represented by Formula (1-1): CF.sub.3CHXCHX.sub.2, wherein each X is independently H or Cl, with the proviso that at least one X represents Cl, and a chlorine-containing alkene represented by Formula (1-2): CF.sub.3CXCX.sub.2, wherein each X is independently H or Cl, with the proviso that at least one X represents Cl, to a gas-phase oxychlorination reaction in a temperature range of 380 C. or lower in the presence of oxidative gas and hydrogen chloride gas.