In recent years, narcissism has been attracting considerable interest by researchers because of its enigmatic constructs. To enhance our understanding of narcissists’ psychosocial functioning, considering the relationship between narcissism and interpersonal trust is crucial. This study aimed to investigate how narcissistic admiration and rivalry are associated with interpersonal trust. To gain a more nuanced understanding, a cross‐lagged design was conducted at two time points that were six months apart. In total, 357 adolescents (M
age = 16.33 years) completed the Narcissistic Admiration and Rivalry Questionnaire (NARQ) and the Interpersonal Trust Scale. The results showed that narcissistic admiration positively predicted interpersonal trust while narcissistic rivalry negatively predicted interpersonal trust at the second time point. However, interpersonal trust did not predict subsequent levels of narcissistic admiration and rivalry. These findings enhanced our understanding by showing that narcissistic admiration and rivalry have different effects on interpersonal trust, and that they remain relatively stable during a six‐month period.