A fabricating process for an embedded circuit structure is provided. A through hole is formed in a core panel and penetrates the core panel. Two indent patterns are respectively formed on two opposite surfaces of the core panel. A conductive material is electroplated into the through hole and the indent patterns, so as to form a conductive channel in the through hole and two circuit patterns in the indent patterns respectively. Portions of the circuit patterns, which exceed the indent patterns respectively, are removed for planarizing the circuit patterns to be level with the two surfaces of the core panel respectively.