This study investigated if and how children and teachers differ in their assessment of victim‐aggressor relationships in kindergartens. Self‐, peer, and teacher reports of victimization‐aggression networks (who is victimized by whom) were investigated in 25 Swiss kindergartens with 402 5‐ to 7‐years‐old. It was examined whether child characteristics (sex and parent‐reported internalizing and externalizing behavior) influence informant reports of victimization and/or aggression. Findings from statistical network models indicated higher concordance between self and peer reports than between one of these and teacher reports. Results further showed more agreement among informants on aggressors than on victims. Aggressors reported by self and peer reports were low on internalizing behavior, and aggressors reported by self and teacher reports were high on externalizing behavior; teacher‐reported victims were also high on externalizing behavior. Internalizing behavior was unrelated to victimization. According to self and peer reports, boys as well as girls were victimized by boys and girls equally; teachers reported less cross‐sex victimization than same‐sex victimization. The different views of teachers and children on victim‐aggressor relationships have implications for the identification of aggression in early childhood. Mutual sharing of information between children, their parents, peers, and teachers may contribute to signaling victims and aggressors in the early school years.