Proxy caches are essential to improve the performance of World Wide Web and to enhance user perceived latency. In this paper, we propose a new Web object based policy to manage the storage system of a proxy cache. We propose two techniques to improve the storage system performance. The first technique is concerned with prefetching the related files belonging to a Web object, from the disk to main memory. This prefetching improves performance as most of the files can be provided from the main memory instead of proxy disk. The second technique stores the Web object members in contiguous disk blocks in order to reduce the disk access time. This in turn reduces the disk response time. We have used trace-driven simulations to study the performance improvements one can obtain with these two techniques.