Although A Passage to India written by E. M. Forster is a modern novel, the existing studies have not cast light on it in terms of narrative technique, epiphany, which has been regarded as James Joyce’s exclusive property. In the cave scene, one of the most important scenes of the novel, Mrs. Moore hears the echo of the cave, “Bou-Oum, Ou-Boum” and falls into extreme skepticism. It is necessary to examine whether Mrs. Moore’s consistent attitude toward the symbol of “Bou-Oum, Ou-Boum” with extreme skepticism and the existing criticism interpreting this as isolation and disconnection between men are both reductionist attitudes of overlooking the indirectness, polysemy, ambiguity or antinomy of the symbol. This study reads the cave’s echo, “Bou-Oum, Ou-Boum” as an epiphany to look into how the issues such as imperialism in India and the United Kingdom and the importance of individuals bound up in the problems of integration and separation are revealed through an epiphany.