A swirling flow generator for gas-liquid separation for separating a liquid and a gas from gas-liquid two-phase fluid by centrifugal force, the swirling flow generator comprising: a swirling flow generating ribbon for swirling the gas-liquid two-phase fluid, the swirling flow generating ribbon formed from a helically twisted plate member; and a pipe that receives the swirling flow generating ribbon and comprises an inner surface to which a separated liquid is guided, wherein the swirling flow generating ribbon comprises, in a terminal end at a side where the gas-liquid two-phase fluid flows out, a first terminal end point that is in a first end of radially outward ends of the swirling flow generating ribbon ; a second terminal end point that is in a second end of radially outward ends of the swirling flow generating ribbon ; a middle terminal end point that is on an axial line (O) of the swirling flow generating ribbon and at a location closer to a side where the gas-liquid two-phase fluid flows in the swirling flow generating ribbon than the first terminal end point and the second terminal end point ; a terminal line (L) between the first terminal end point and the second terminal end point is perpendicular to the axial line (O) of the swirling flow generating ribbon ; a first terminal edge connecting the first terminal end point and the middle terminal end point ; a second terminal edge connecting the second terminal end point and the middle terminal end point , characterized in that in the terminal end of the swirling flow generating ribbon , a V shaped space or area is defined by the first terminal edge , the second terminal edge , and the terminal line (L), wherein the swirling flow generating ribbon comprises a folding back structure in the first terminal edge and the second terminal edge , the folding back structure being folded back toward the side where the gas-liquid two-phase fluid flows in the swirling flow generating ribbon . a swirling flow generating ribbon for swirling the gas-liquid two-phase fluid, the swirling flow generating ribbon formed from a helically twisted plate member; and a pipe that receives the swirling flow generating ribbon and comprises an inner surface to which a separated liquid is guided, wherein the swirling flow generating ribbon comprises, in a terminal end at a side where the gas-liquid two-phase fluid flows out, a first terminal end point that is in a first end of radially outward ends of the swirling flow generating ribbon ; a second terminal end point that is in a second end of radially outward ends of the swirling flow generating ribbon ; a middle terminal end point that is on an axial line (O) of the swirling flow generating ribbon and at a location closer to a side where the gas-liquid two-phase fluid flows in the swirling flow generating ribbon than the first terminal end point and the second terminal end point ; a terminal line (L) between the first terminal end point and the second terminal end point is perpendicular to the axial line (O) of the swirling flow generating ribbon ; a first terminal edge connecting the first terminal end point and the middle terminal end point ; a second terminal edge connecting the second terminal end point and the middle terminal end point , characterized in that in the terminal end of the swirling flow generating ribbon , a V shaped space or area is defined by the first terminal edge , the second terminal edge , and the terminal line (L), wherein the swirling flow generating ribbon comprises a folding back structure in the first terminal edge and the second terminal edge , the folding back structure being folded back toward the side where the gas-liquid two-phase fluid flows in the swirling flow generating ribbon . <EOS>