Method for producing a metal-resin composite

Provided are a metal-resin composite having excellent adhesive strength, a method for producing the same, a busbar, a module case, and a resinous connector part. The metal-resin composite comprises a metallic member 1 including a metal with a high melting point of 500°C or more, a resin member 2 being integrated with the metallic member 1; and an alloy layer 3 including a metal with a low melting point lower than 500°C. The alloy layer 3 is arranged between the metallic member 1 and the resin member 2, and has average surface roughness thereof in the range from 5nm or more to less than 1 µm at the interface between the alloy layer 3 and the resin member 2. Herein, a period of the unevenness formed on the interface of the alloy layer 3 is in the range from 5nm or more to less than 1 µm.