In this paper we introduce and evaluate two prefetching techniques to improve the performance of Java applications executed on the grid. These techniques are experimentally evaluated on two grid environments, by running test applications on two different grid deployment configurations. Our testbed is SUMA/G, a grid platform specifically targeted at executing Java bytecode on Globus grids. The experimental results show that these techniques can be effective on improving the performance of applications run on the grid, especially for compute intensive scientific applications.