Rejection sensitivity is a bias toward expecting rejection that can result from negative social experiences and degrade emotional adjustment. In this study, rejection sensitivity was expected to predict patterns of adolescent social anxiety over 5 years when considered alongside other known or expected risk and protective factors: peer rejection (peer-reported), emotion dysregulation, self-worth, temperament (parent-reported), female gender, and grade. Participants were 377 Australian students (45% boys; 79% White, 15% Asian) aged 10 to 13 years (M = 12.0, SD = 0.90) and their parents (84%) who completed seven repeated surveys across 5 years. In an unconditional latent growth model, social anxiety symptoms had a significant quadratic pattern of growth, with symptoms increasing about midway into the study when adolescents were age 14, on average. In a model with all predictors, rejection sensitivity was uniquely associated with a higher intercept and a more pronounced quadratic growth pattern of social anxiety symptoms. Other predictors of growth in symptoms were the temperamental trait of negativity affectivity and emotion dysregulation; negative affectivity was associated with a higher intercept and a more pronounced quadratic pattern, and emotion dysregulation was associated with a higher intercept and a less pronounced quadratic pattern. Gender was associated with the intercept, with girls higher in symptoms than boys.