Currently, there are many system requirements to guarantee the sealability, fault-tolerance, and high performance in the rapidly evolving research fields such as Grid and P2P technologies. Due to the dynamic nature of the Grid computing and P2P in networks, the behavior of system might be very unpredictable in respect of reliability. In this paper, we propose the Group Peer based P2P Grid system architecture with k-Redundancy Scheme(1) that can satisfy these requirements. With respect to load balancing, this P2P Grid system clearly shows that redundancy scheme of group peer guarantees the reliability for resource or service discovery. Through the theoretical analysis and simulation, we discuss the performance of the proposed scheme.