In China, grandparents play a significant role in childrearing. This study aims to identify latent profiles of intergenerational parenting styles and explore their impact on grandchildren’s behavioral outcomes. A total of 1432 Chinese children (M_age = 12.58 years; 45.25% boys) completed questionnaires assessing perceived grandparenting styles, while fathers and mothers independently reported their own parenting practices. Latent Profile Analysis (LPA) identified three distinct parenting profiles: “Grandparents Positive–Parents Negative” (GP–PN, 18.37%), “Grandparents Positive–Parents Positive” (GP–PP, 59.15%), and “Grandparents Negative–Parents Positive” (GN–PP, 22.48%). Regression analyses revealed that the number of siblings, grade level, and grandparent type could significantly predict profile membership. Notably, consistent and positive intergenerational parenting styles were associated with fewer problem behaviors in children. Furthermore, the relationship between parenting profiles and problem behaviors was mediated by the quality of the grandparent–parent relationship. These findings suggested that grandparents and parents should coordinate their parenting styles when raising grandchildren together.