A multilayer circuit board (1) includes resin bases (101 to 10N) stacked while placing separators (121 to 12N−1) in between, interconnect patterns (111 to 11N) respectively formed on one surface of each of the resin bases (101 to 10N), and electro-conductive bumps (201 to 20N−1) which electrically connect the interconnect patterns (111 to 11N). The resin bases (101 to 10N) and the separators (121 to 12N−1) are heat-bonded, the separators (121 to 12N−1) are composed of a first thermoplastic resin material having a first glass transition temperature, and the resin bases (101 to 10N) are composed of a second thermoplastic resin material having a second glass transition temperature higher than the first glass transition temperature.