A solar cell and a solar cell module are disclosed. The solar cell includes a semiconductor substrate, an emitter region extending in a first direction, a back surface field region extending in the first direction in parallel with the emitter region, a first electrode connected to the emitter region and extending in the first direction, and a second electrode connected to the back surface field region and extending in the first direction. The first electrode has different linewidths at two positions that are separated from each other in the first direction. The second electrode has different linewidths at two positions that are separated from each other in the first direction. A linewidth of the first electrode and a linewidth of the second electrode are different from each other at two positions that are separated from each other in a second direction crossing the first direction.