To provide a laser welding method of a copper lead wire and a fuse element with low melting point, by which cooling and solidifying period of melted fuse element part and total welding period are shortened.

Tin is coated on a flat surface part of the copper lead wire. The tin coated layer is melted when the laser is irradiated. Alloying of a contact interface of the melted coating layer and the melted fuse element is promoted to heighten the contact strength. Even if wet-spread of the melted fuse element part is small, namely, even if heating period is short, the contact interface is imparted with sufficient strength. Accordingly, heating period can be shortened and heating temperature can be lowered to that extent, and a period until the melted part of the fuse element is cooled and solidified can be shortened to that extent. As a result, total period of laser welding can be shortened.