In a structure for connecting a semiconductor element having a fine pitch electrode at 50 μm pitch or less and a pad or wirings on a substrate, for preventing inter-bump short-circuit or fracture of a connected portion due to high strain generated upon heating or application of load during connection, the substrate and the semiconductor element are connected by way of a bump having a longitudinal elastic modulus (Young's modulus) of 65 GPa or more and 600 GPa or less and a buffer layer including one of tin, aluminum, indium, or lead as a main ingredient and, further, protrusions are formed to at least one of opposing surfaces of the bump and the pad or the wirings on the substrate to each other, and the surfaces are connected by ultrasonic waves.