A method of fabricating a semiconductor package is provided, including: disposing a semiconductor element on a carrier; forming an encapsulant on the carrier to encapsulant the semiconductor element; forming at least one through hole penetrating the encapsulant; forming a hollow conductive through hole in the through hole and, at the same time, forming a circuit layer on an active surface of the semiconductor element and the encapsulant; forming an insulating layer on the circuit layer; and removing the carrier. By forming the conductive through hole and the circuit layer simultaneously, the invention eliminates the need to form a dielectric layer before forming the circuit layer and dispenses with the conventional chemical mechanical polishing (CMP) process, thus greatly improving the fabrication efficiency.