To improve the reliability of a solder connection part when a package component without a lead is mounted on a printed board.

The number of cycles of a high/low temperature cycle test can be extended by increasing the thickness of an electrode connecting solder by a component supporting solder pattern which is not an electrode and a component supporting solder, or by eliminating a large portion of a pattern of printed board inner layers (2, 3 layers) immediately below the package component without a lead, or by extending a large portion of a signal lead-out pattern of the package component 2 without a lead to an opposite surface of a mounting surface of the package component 2 without a lead through a via hole except a land part for a component electrode, or by connecting layers of a component supporting solder pattern 4b which is not a component electrode by means of a plurality of via holes, or by relaxing stress generated by a linear expansion difference in a temperature variation by disposing a via hole near the package component without a lead symmetrically to a component central line.