Proxy Mobile IPv6 (PMIPv6) is a network-based mobility support protocol and it does not require MNs to be involved in the mobility support signaling. In flow mobility support, although the virtual interface in the MN solved the problems of vertical handover or flow mobility in heterogeneous network, missing procedure of MN-derived flow handover makes flow mobility in PMIPv6 incomplete. In this paper, enhanced flow mobility support is proposed for actualizing and full-covering of the flow mobility support in PMIPv6. Enhanced flow mobility support is based on a virtual interface in the MN. Virtual interface makes all physical interfaces to hide from the network layer and above. Flow Interface Manager is placed at the virtual interface and Flow Binding Manager in the LMA is paired with Flow Interface Manager. They manage the flow bindings and are used to select proper access technology to send packets. Flow mobility procedure begins with three different triggering cases, which are caused by new connection from the MN, the LMA's decision, and request from the MN, respectively. Simulation using NS-3 network simulator is performed to provide clear and practical procedure of enhanced flow mobility support in PMIPv6.