A method for recovering olefin, comprising: an olefin concentrating process of supplying a part or all of an olefin-containing gas containing olefin to an olefin-containing-gas separating unit that includes a separation membrane and causing the olefin-containing gas to transmit the separation membrane, so as to obtain an olefin concentrated gas reduced in mol concentration of a component other than olefin to 1/10 or less compared with a mol concentration of a component other than olefin in the olefin-containing gas; a residual-gas combustion process of disposal of residual gas that does not transmit the separation membrane in the olefin concentrating process by burning, wherein the separation membrane is a membrane consisting of: an inorganic framework containing at least one of components selected from the group consisting of carbon, silica, titania, alumina, and zirconia; and a metallic element with olefin selectivity, the metallic element being dispersed in the inorganic framework, wherein the metallic element with olefin selectivity is at least one of silver and copper, and wherein a ratio (A/B) between: a standard deviation of concentration of the metallic element; and an average value of concentration of the metallic element, in the separation membrane is equal to or less than 0.7, wherein the concentration of the metallic element is measured at a magnification of 2000 times at ten points on the surface of the separation membrane at intervals of 100 μm by energy dispersive X-ray spectrometry. an olefin concentrating process of supplying a part or all of an olefin-containing gas containing olefin to an olefin-containing-gas separating unit that includes a separation membrane and causing the olefin-containing gas to transmit the separation membrane, so as to obtain an olefin concentrated gas reduced in mol concentration of a component other than olefin to 1/10 or less compared with a mol concentration of a component other than olefin in the olefin-containing gas; a residual-gas combustion process of disposal of residual gas that does not transmit the separation membrane in the olefin concentrating process by burning, wherein the separation membrane is a membrane consisting of: an inorganic framework containing at least one of components selected from the group consisting of carbon, silica, titania, alumina, and zirconia; and a metallic element with olefin selectivity, the metallic element being dispersed in the inorganic framework, wherein the metallic element with olefin selectivity is at least one of silver and copper, and wherein an inorganic framework containing at least one of components selected from the group consisting of carbon, silica, titania, alumina, and zirconia; and a metallic element with olefin selectivity, the metallic element being dispersed in the inorganic framework, wherein the metallic element with olefin selectivity is at least one of silver and copper, and wherein a ratio (A/B) between: a standard deviation of concentration of the metallic element; and an average value of concentration of the metallic element, in the separation membrane is equal to or less than 0.7, wherein the concentration of the metallic element is measured at a magnification of 2000 times at ten points on the surface of the separation membrane at intervals of 100 μm by energy dispersive X-ray spectrometry.