The rapid progress of biotechnology provides an increasing number of life science databases. These databases have been operated and managed individually on the Internet. Under such a circumstance, it is needed to develop an infrastructure that allows to share information contained in these databases and to conduct research collaboration. Grid technology is an emerging technology for seamless and loose integration of diverse resources distributed on the Internet. In order to achieve federation of the heterogeneous databases, we have developed a system for supporting a drug discovery process using Globus Toolkit3/OGSA-DAI. As an essential part of the system, we introduce a protein-compound interaction search based on a meta-data bridging protein and compound information with their interaction types; such as, inhibitor, agonist, antagonist, etc. The effectiveness of our system is demonstrated by searching for the candidate compounds interacting with the glucocorticoid receptor protein.