A semiconductor package includes a substrate, a device die, an encapsulating material, a thermal conductive layer, a filling material, and a carrier. The device die is disposed over the substrate. The encapsulating material is disposed over the substrate and laterally encapsulates the device die. The thermal conductive layer conformally covers the device die and the encapsulating material, wherein a profile of the thermal conductive layer comprises a valley portion. The filling material is disposed over the thermal conductive layer and fills the valley portion, wherein a thermal conductivity of the thermal conductive layer is higher than a thermal conductivity of the filling material. The carrier is bonded to the thermal conductive layer and the filling material.