Production process of hydrofluorocarbons

A process for producing a hydrogen-containing fluorinated hydrocarbon in which at least one halogenated hydrocarbon reaction raw material which is selected from the group consisting of a chlorinated alkene and a hydrogen-containing chlorinated alkane is subjected to a fluorination reaction with a hydrogen fluoride reaction raw material in a liquid phase in a reactor in the presence of a fluorination catalyst so as to obtain a reaction mixture which comprises the hydrogen-containing fluorinated hydrocarbon as a reaction product, which process comprises using the reactor having a reactor portion which is able to contact with the reaction mixture, at least a part of the reactor portion being made of an alloy material of 18 to 20% by weight of chromium, 18 to 20% by weight of molybdenum, 1.5 to 2.2% by weight of at least one element selected from niobium and tantalum and the balance of nickel.