PROBLEM TO BE SOLVED: To provide a lead wire for a solar cell having excellent flex fatigue characteristics in which the solar cell (e.g. a silicon cell) is less susceptible to warpage or damage when bonding the lead wire even if the solar cell is made thin.SOLUTION: In the lead wire for a solar cell where the surface of a conductor is coated partially or entirely with plating, crystal grain size of the conductor is set in the range of 6-20 μm, 0.2% proof stress in tensile test is set to 90 MPA or lower, and the thickness of an oxide film on the surface of the conductor is set to 2 nm or thinner.