On a self-healing wire using an electric field trapping of gold nanoparticles, we examined a particle size dependence of a healing voltage by comparing 20 nm and 200 nm in particle radii. We fabricated the gold wires with a patterned crack on a glass substrate, and measured the healing voltages. As a result, in the each case of 20 nm and 200 nm in particle radii, cracks up to 1000 nm were healed by applying under 3.2 V in amplitude of AC voltage, and cracks up to 3500 nm were healed by applying under 4.0 V in amplitude of AC voltage, respectively. This result shows that the case of 200 nm in particle radius can heal a larger crack by applying the same voltage than the case of 20 nm in particle radius.