An electrical connecting portion for a device with a heating function is a portion of a heating unit of the device. The electrical connecting portion includes a substrate, two copper layers, and two electrically conductive coating layers. The substrate is made of a light-transmittable material and includes a front face and a rear face. Each of the two copper layers includes at least one first through-hole extending in a front-rear direction. Each of the two electrically conductive coating layers substantially covers a respective one of the two copper layers and is coupled to the front face of the substrate. Each of the two electrically conductive coating layers substantially fills the at least one first through-hole of the respective one of the two copper layers. The two electrically conductive coating layers have an insulating spacing therebetween. Thus, the electrical connecting portion prevents hot melting and provides better electrical connection reliability.