The purposes of the present study were to investigate the factor structure of the perception of relational aggression, that is, children’s knowledge structure about relational aggression, and to examine the relation between the participants’ perception of relational aggression and aggressive behavior.  The participants (446 elementary school students) completed a questionnaire that included provisional items about their perception of relational aggression, their experiences with relational aggression, and the Proactive-Reaction Aggression Questionnaire (PRAQ).  In addition, 163 of the children completed the questionnaire again at a later time. Factor analysis yielded 4 factors : negative perception of relational aggression, familiarity, justification, and usefulness.  The reliability of the Perception of Relational Aggression Scale, examined by measures of internal consistency, was found to be almost acceptable.  High test-rest reliability was found in the data of the children who completed the instrument on 2 occasions.  The validity of the scales was examined in relation to the association between perception and experience.  Finally, multiple regression analysis revealed that the children’s perception of relational aggression was significantly associated with relational aggression, even when reactive-expressive aggression was controlled.