A package structure includes a semiconductor die, conductive pillars, an insulating encapsulation, a redistribution circuit structure, and a solder resist layer. The conductive pillars are arranged aside of the semiconductor die. The insulating encapsulation encapsulates the semiconductor die and the conductive pillars, and the insulating encapsulation has a first surface and a second surface opposite to the first surface. The redistribution circuit structure is located on the first surface of the insulating encapsulation. The solder resist layer is located on the second surface of the insulating encapsulation, wherein a material of the solder resist layer includes a filler.