A package structure includes a first package, a second package, a conductive spacer, and a flux portion. The first package includes a semiconductor die. The second package is stacked to the first package. The conductive spacer is disposed between and electrically couples the first package and the second package. The flux portion is disposed between and electrically couples the first package and the conductive spacer, where the flux portion includes a first portion and a second portion separating from the first portion by a gap, and the first portion and the second portion are symmetric about an extending direction of the gap. The gap is overlapped with the conductive spacer.