A solar cell element, comprising: a semiconductor substrate that comprises a semiconductor region of one conductivity type and a layer of an opposite conductivity type to the one conductivity type with a first surface serving as a light-receiving surface, a second surface located on a back side of the first surface, and a side surface connecting the first surface and the second surface, in which over a surface on the first surface side, a surface on the side surface side and a surface of an outer peripheral portion on the second surface side of the semiconductor region of the one conductivity type, the layer of the opposite conductivity type to the one conductivity type is formed such that a first pn junction is provided along the respective surfaces of the first surface, the side surface and the outer peripheral portion of the second surface; and a first electrode of the one conductivity type located on the second surface and connected to the semiconductor region of the one conductivity type so as to be adjacent to the first pn junction region, wherein the semiconductor substrate includes a first trench portion located between the outer periphery of the second surface and an end portion of the first electrode with a space from the first electrode and configured to isolate the first pn junction region on the second surface along the outer periphery of the second surface; and when viewed from the second surface side in plan view, a shortest distance Q between the end portion of the first electrode and the first trench portion is smaller than a shortest distance P between a pn junction of the first pn junction region of the side surface side and the first trench portion. a semiconductor substrate that comprises a semiconductor region of one conductivity type and a layer of an opposite conductivity type to the one conductivity type with a first surface serving as a light-receiving surface, a second surface located on a back side of the first surface, and a side surface connecting the first surface and the second surface, in which over a surface on the first surface side, a surface on the side surface side and a surface of an outer peripheral portion on the second surface side of the semiconductor region of the one conductivity type, the layer of the opposite conductivity type to the one conductivity type is formed such that a first pn junction is provided along the respective surfaces of the first surface, the side surface and the outer peripheral portion of the second surface; and a first electrode of the one conductivity type located on the second surface and connected to the semiconductor region of the one conductivity type so as to be adjacent to the first pn junction region, wherein the semiconductor substrate includes a first trench portion located between the outer periphery of the second surface and an end portion of the first electrode with a space from the first electrode and configured to isolate the first pn junction region on the second surface along the outer periphery of the second surface; and when viewed from the second surface side in plan view, a shortest distance Q between the end portion of the first electrode and the first trench portion is smaller than a shortest distance P between a pn junction of the first pn junction region of the side surface side and the first trench portion.