Periodical appearance of irritating events in the relations between Peru and Chile contributes to perpetuate an instability that keeps stagnant the possibilities of a broader Peruvian-Chilean cooperation. This has been studied by various disciplines and multiple approaches throughout history, but psycho-social analysis is scarce. In order to try to understand the intergroup dynamics between Peru and Chile, the present study analyzes the relations between political ideology, national identity, stereotypical representations and the exogrupal assessment of Peruvians and Chileans as factors associated with them. The sample is made up of 223 people in Peru and 196 people in Chile. The results suggest that conservative ideologies are negatively related to stereotypical representations and exogrupal assessment. This is particularly clear in the case of authoritarianism. Likewise, a positive self-stereotypical representation will tend to positively influence the stereotypical representation of the corresponding national exogroup.