Provided is a method of welding capable of producing a weld joint having a sufficient strength by selecting metallic glass that satisfies predetermined requirements and crystalline metal. The method of welding of the present invention comprising giving energy to the metallic glass-crystalline metal border or to the metallic glass adjacent to the border to heat the metallic glass so that a molten layer is formed, characterized in that the molten layer at a joint between the metallic glass and the crystalline metal has glass-forming ability, in that the metallic glass has glass-forming properties such that the nose time of the TTT curve when the solid metallic glass is reheated is 0.2 sec or more, and in that the metallic glass and the crystalline metal are configured from materials such that the difference between the melting point of the crystalline metal and the temperature at which the solid crystalline metal and the molten metal glass exhibit a spread factor of 25% or higher is 100K or more.