Romeo learns of Juliet's love in Act 2, sc. 2, when he overhears her profess her feelings while he is in her garden the night they met. She doesn't know he's there and she is just expressing her thoughts out loud and she says that it is only his name that stands between them. She says that if he weren't a Montague there would be nothing to interfere with their love and so if he could just get rid of his name, he could have all of her. Upon hearing this declaration of love, Romeo reveals himself to her and declares his love for her. The two then plan to get married.