A package structure includes a wafer-form semiconductor package and a thermal dissipating system. The wafer-form semiconductor package includes semiconductor dies electrically connected with each other. The thermal dissipating system is located on and thermally coupled to the wafer-form semiconductor package, where the thermal dissipating system has a hollow structure with a fluidic space, and the fluidic space includes a ceiling and a floor. The thermal dissipating system includes at least one inlet opening, at least one outlet opening and a plurality of first microstructures. The at least one inlet opening and the at least one outlet opening are spatially communicated with the fluidic space. The first microstructures are located on the floor, and at least one of the first microstructures is corresponding to the at least one outlet opening.