This paper describes newly developed thermally conductive circuit board. The board consists of an anodized aluminum substrate, which is coated with electrodeposited acrylic-melamine polymer.Both anodized aluminum and electrodeposited polymer work as insulating layers between aluminum core and electrical circuitry. Polymer thick film (PTF) is adopted as circuitization in the board. This paper describes manufacturing process and evaluation results of the board from the viewpoint of both electrical and thermal reliability. Two of prototype models for power application are demonstrated in this paper.