TWI642332B

Provided are both a flexible printed board, in which heat dissipation performance can be improved in without using an aluminum heal dissipating material, which is light in weight, has good processability and can be reduced in cost, and a method for manufacturing such a flexible printed board. The flexible printed board is a flexible printed board 10 on which a power consuming load is mounted, including: a front surface heat dissipation layer 30 made of a copper foil and having a circuit portion on which the load is mounted; a thermally conductive resin layer 20 having the front surface heat dissipation layer 30 laminated to a front surface side thereof and having a thermal conductivity of 0.49 W/mK or more; and a rear surface heat dissipation layer made of a copper foil, laminated to a rear surface side of the thermally conductive resin layer 20, and having a thickness of 100 to 400% with respect to the front surface heat dissipation layer 30.