An apparatus and a method to perform a fast handover that is capable of determining whether to switch an internet protocol (IP) using a received, unique code of an access router when a mobile node performs a fast handover in a wireless network. The apparatus to perform a fast handover includes a signal receiving unit to receive a signal, a subnet change determining unit to determine if a subnet change has occurred by referring to an access router identification (ID) included in the received signal, a trigger unit to perform a layer trigger depending upon the determination result as to whether a subnet change has occurred, and a handover performing unit to perform a handover according to the layer trigger.