Web caching has been well accepted as a viable method for saving network bandwidth and reducing user access latency. To provide cache sharing on a large scale, hierarchical web caching has been widely deployed to improve the scalability of content dissemination through the World Wide Web. In this paper, we present GHC, a grid-based hierarchical web caching architecture, for constructing efficient cache hierarchy in Grid environment. Basing on the GHC architecture, we also proposed HCPR algorithm, which is a novel coordinated placement and replacement algorithm for hierarchical web caching scheme. The principle of HCPR algorithm is to improve cache usage, to cache hot document close to clients so as to minimize the number of hops to locate and access Web documents. The simulation study shows that the HCPR algorithm has higher cache hit ratio and lower access latency compared with the traditional hierarchical caching algorithms.