[Problem] To reduce the mismatching of impedance at a connected part when electronic components are electrically connected to each other. [Solution] An electronic components assembly, wherein electronic components (1, 2) are electrically connected to each other, and wherein a wiring line (11) formed the surface (1a) of the first electronic component (1) and a wiring line (12) formed on the surface (2a) of the second electronic component (2) face each other and are bonded to each other through an electrically conductive material (13), thereby electrically connecting the first electronic component (1) to the second electronic component (2). The electrically conductive material (13) is a resin composition containing a solder or an electrically conductive filler.