In a printed-wiring board, first and second hard substrates each having electronic components mounted thereon are connected through a flexible substrate interposed therebetween. A circuit pattern printed on each of the hard and flexible substrates electrically connects the electronic components mounted on the hard substrates through the flexible substrate. The circuit pattern includes a plurality of parallel-connected signal lines. The parallel-connected signal lines are spatially separated on the flexible substrate, and the both ends of the parallel-connected signal lines are located in the hard substrates, respectively. A single signal line of the circuit pattern branches on one hard substrate into the parallel-connected signal lines, which extend through the flexible substrate and are converged to a single signal line on the other hard substrate.