Adolescents' depressive symptoms are affected by a number of factors including life stress, gender, socio-economic status, and parental depression symptoms. However, little is known about whether adolescent depressive symptoms are also affected by parental motivational characteristics. The current study explores the relationship between parental motivational perseverance (i.e., parents' persistency in the face of setbacks and difficulties) and children's depressive symptoms during the adolescence, given the critical role of perseverance in psychological well-being. The predictive utility of two motivational characteristics relevant to perseverance: parents' growth mindset (i.e., one's belief about the malleability of human competence) and grit (i.e., perseverance for long term goals) were examined. Four hundred pairs of Japanese parents (82% mothers) and their adolescent children (50% females; average age at the time of the first assessment = 14.05 years; SD = 0.84) independently completed surveys measuring their growth mindset, grit, and depressive symptoms at two time points (approximately one year apart; attrition rate = 25%). The Actor-Partner Independence Model, a statistical model that accounts for inter-dependence between dyads (e.g., parents and children), was used to examine how parental motivational perseverance predicts the long-term change in their offspring's depressive symptoms. The results showed that parental grit led to the decrease in adolescents' depressive symptoms through the changes in adolescents' grit. On the other hand, parental growth mindset directly predicted the adolescents' depressive symptoms, and this was not mediated by the adolescents' growth mindset. These findings underscore the importance of parental motivational characteristics in regards to adolescents' depressive symptoms.