Various embodiments relate to a circuit board, including a base and a heat-conducting layer. The base has a first region and a second region on one side thereof facing the heat-conducting layer, the first region is recessed with respect to the second region, a first insulating layer is accommodated in the first region, a second insulating layer is formed on the second region, and the first insulating layer and the second insulating layer have different thermal conductivities. In addition, various embodiments further relate to an electronic module and an illuminating device including such circuit board. Various embodiments also relate to a method for manufacturing such circuit board.