A method for manufacturing hydrofluoroolefin, includes: converting hydrofluorocarbon represented by a formula (1) into hydrofluoroolefin (HFO) represented by formula (2) in the presence of carbon dioxide to obtain a first gas composition containing hydrofluoroolefin and carbon dioxide; and separating carbon dioxide contained in the first gas composition to obtain a second gas composition containing HFO, CR1R2X1CR3R4X2 . . . (1), CR1R2═CR3R4 . . . (2), wherein R1 to R3 are each independently hydrogen atom or fluorine atom, R4 is hydrogen atom, fluorine atom, CH3, CH2F, CHF2 or CF3, the total number of fluorine atoms of R1 to R4 is one or more, and the total number of hydrogen atoms of R1 to R4 is one or more, X1 and X2 are each hydrogen atom or fluorine atom where X2 is the fluorine atom when X1 is the hydrogen atom, and X2 is the hydrogen atom when X1 is the fluorine atom.