Design support system for printed circuit board, design support method, program, and recording medium

This design support system selects and determines a bypass capacitor to be mounted on a substrate from among a plurality of bypass capacitors (C1-C12), and is provided with: a connection path calculation unit (103) that calculates a connection path for all combinations of a plurality of power supply terminals (1V) of a semiconductor integrated circuit device and one electrode of the plurality of bypass capacitors (C1-C12); the shortest distance calculation unit calculates the shortest distance in a wiring path from a connection position of a power supply wiring layer to which each of a plurality of power supply terminals (1V) of the semiconductor integrated circuit device (1) is connected to a power supply side wiring layer to which one electrode of each of a plurality of bypass capacitors (C1-C12) is connected. And a validity evaluation unit (104) that, for each of the plurality of power supply terminals, performs a relative comparison of the shortest distances of the wiring paths in the substrates correspon