In the recent years, Peer-to-Peer (P2P) sharing network has become very popular in the Internet. However, most P2P protocols are designed for traditional wired networks. When deployed in wireless network environment, many challenges are encountered. For instance, the nodes in an unstable wireless network tend to leave or rejoin the P2P network easily. In this case, the routing information in every node must become overdue, which may lead to lookup failures when the nodes retrieve these overdue routing information. In this paper, we propose a modified Chord protocol called MobileRobust-Chord (MR-Chord). MR-Chord is designed with the aim of keeping the Finger Table fresh. To achieve this goal, we have modified the Distributed Hash Table (DHT)-based protocol a Chord Protocol in such a way that the Finger Table is kept updated to provide the necessary lookup services in the P2P network. Simulations studies show that our proposed MR-Chord protocol outperforms the original Chord protocol in the following aspects: (1) increase in the lookup success rate and overlay consistency, (2) reduction of the lookup delay time.