A solar cell comprising: a photoelectric conversion unit having first and second main surfaces, a first electrode provided on the first main surface, and a second electrode provided on the second main surface; the first electrode having: a plurality of finger portions extending in a first direction and arrayed in a second direction perpendicular to the first direction leaving gaps therebetween, and a busbar portion connected electrically to the plurality of finger portions; characterized by further comprising a plurality of protruding portions provided on the first main surface, protruding from the busbar portion on at least one side of the busbar portion in the first direction, the plurality of protruding portions provided so that the total perimeter of the protruding portions per unit area in an end portion of the first main surface in the second direction is longer than the total perimeter of the protruding portions per unit area in the central portion of the first main surface in the second direction and thereby increasing a bonding strength of a wiring material to the solar cell in the end portion, wherein the plurality of protruding portions includes a protruding portion having a linear portion extending in the first direction. a photoelectric conversion unit having first and second main surfaces, a first electrode provided on the first main surface, and a second electrode provided on the second main surface; the first electrode having: a plurality of finger portions extending in a first direction and arrayed in a second direction perpendicular to the first direction leaving gaps therebetween, and a busbar portion connected electrically to the plurality of finger portions; characterized by further comprising a plurality of protruding portions provided on the first main surface, protruding from the busbar portion on at least one side of the busbar portion in the first direction, the plurality of protruding portions provided so that the total perimeter of the protruding portions per unit area in an end portion of the first main surface in the second direction is longer than the total perimeter of the protruding portions per unit area in the central portion of the first main surface in the second direction and thereby increasing a bonding strength of a wiring material to the solar cell in the end portion, wherein the plurality of protruding portions includes a protruding portion having a linear portion extending in the first direction. a plurality of finger portions extending in a first direction and arrayed in a second direction perpendicular to the first direction leaving gaps therebetween, and a busbar portion connected electrically to the plurality of finger portions; characterized by further comprising a plurality of protruding portions provided on the first main surface, protruding from the busbar portion on at least one side of the busbar portion in the first direction, the plurality of protruding portions provided so that the total perimeter of the protruding portions per unit area in an end portion of the first main surface in the second direction is longer than the total perimeter of the protruding portions per unit area in the central portion of the first main surface in the second direction and thereby increasing a bonding strength of a wiring material to the solar cell in the end portion, wherein the plurality of protruding portions includes a protruding portion having a linear portion extending in the first direction.