Interpersonal synchronization refers to a spontaneous, unconscious expression of interpersonal congruence. According to existing research, both partners in a romantic relationship show interpersonal synchrony at different levels. Researchers have focused on three aspects of interpersonal synchronization in romantic relationships: behavioral and emotional synchronization, physiological synchronization, and brain synchronization. Future research should be explored from the following four aspects in the field of interpersonal synchronization in romantic relationships: definition of romantic relationships, types of evoked activities, research techniques and monitoring indicators, and potential applications of bonding.