A multi-chip package may include first and second semiconductor chips, an insulating layer structure and a plug structure. The first semiconductor chip may include a first bonding pad. The second semiconductor chip may be positioned over the first semiconductor chip. The second semiconductor chip may include a second bonding pad. The insulating layer structure may cover side surfaces and at least portions of upper surfaces of the semiconductor chips. The plug structure may be formed in the insulating layer structure by a plating process. The plug structure may be arranged spaced apart from side surfaces of the semiconductor chips to electrically connect the first bonding pad and the second bonding pad with each other. A third semiconductor chip having a third bonding pad may be positioned over the second semiconductor chip. Thus, a process for forming a micro bump between the plugs need not be performed.