A polymer electrolyte fuel cell comprising: an electrolyte layer-electrode assembly including an electrolyte layer and a pair of electrodes (4A, 4B) sandwiching the electrolyte layer; a plate-shaped electrically conductive first separator disposed so as to be in contact with one electrode of the pair of electrodes of the electrolyte layer-electrode assembly, wherein one main surface of the first separator is in in contact with the one electrode, the one main surface being provided with a first reaction gas flowing region which is formed in a winding shape and through which a first reaction gas flows, the first reaction gas flowing region including a plurality of groove-shaped first straight line portions and one or more first turn portions; and a plate-shaped electrically conductive second separator disposed so as to be in contact with another electrode of the pair of electrodes of the electrolyte layer-electrode assembly, wherein one main surface of the second separator is in contact with the other electrode, the one main surface being provided with a second reaction gas flowing region which is formed in a winding shape and through which a second reaction gas flows, the second reaction gas flowing region including a plurality of groove-shaped second straight line portions and one or more second turn portions, wherein in the first separator, among the one or more first turn portions, at least one first turn portion is provided with a first recess and a plurality of first projections rising from a bottom surface of the first recess, in the second separator, among the one or more second turn portions, at least one second turn portion is provided with a second recess and a plurality of second projections rising from a bottom surface of the second recess, and characterized in that when seen in a thickness direction of the first separator, an overlap area is less than or equal to 5 % of a gross area, the overlap area being a total overlap area between the first and second recesses (48, 58) provided in the first and second separators (6A, 6B), the gross area being a total of the following areas: an area of all the first recesses provided in the first separator; and an area of all the second recesses provided in the second separator. an electrolyte layer-electrode assembly including an electrolyte layer and a pair of electrodes (4A, 4B) sandwiching the electrolyte layer; a plate-shaped electrically conductive first separator disposed so as to be in contact with one electrode of the pair of electrodes of the electrolyte layer-electrode assembly, wherein one main surface of the first separator is in in contact with the one electrode, the one main surface being provided with a first reaction gas flowing region which is formed in a winding shape and through which a first reaction gas flows, the first reaction gas flowing region including a plurality of groove-shaped first straight line portions and one or more first turn portions; and a plate-shaped electrically conductive second separator disposed so as to be in contact with another electrode of the pair of electrodes of the electrolyte layer-electrode assembly, wherein one main surface of the second separator is in contact with the other electrode, the one main surface being provided with a second reaction gas flowing region which is formed in a winding shape and through which a second reaction gas flows, the second reaction gas flowing region including a plurality of groove-shaped second straight line portions and one or more second turn portions, wherein in the first separator, among the one or more first turn portions, at least one first turn portion is provided with a first recess and a plurality of first projections rising from a bottom surface of the first recess, in the second separator, among the one or more second turn portions, at least one second turn portion is provided with a second recess and a plurality of second projections rising from a bottom surface of the second recess, and characterized in that when seen in a thickness direction of the first separator, an overlap area is less than or equal to 5 % of a gross area, the overlap area being a total overlap area between the first and second recesses (48, 58) provided in the first and second separators (6A, 6B), the gross area being a total of the following areas: an area of all the first recesses provided in the first separator; and an area of all the second recesses provided in the second separator.