This document proposes a conditional graph information bottleneck (CGIB) approach for molecular relational learning tasks. CGIB aims to extract important subgraphs that maximize the preserved information about a molecule's properties while considering the conditional information from another interacting molecule. The method is tested on datasets for molecular interaction prediction tasks like chromophore-solvent absorption and drug-drug interactions. Results show CGIB outperforms baselines at these tasks while providing interpretable important subgraph detections.