Employing integrated threat theory, this inquiry explored how perceived threat, or fear of immigrants, manifests amid early, middle, and late Finnish adolescents, and the relationship between perceived threat and prejudice amid early, middle, and late adolescents. The sample consisted of 795 Finnish adolescents between 11 and 19 years of age. Realistic and symbolic threats were the most perceived threats and were more prevalent amid late adolescents. There was a positive relationship between prejudice and realistic threat, and between prejudice and symbolic threat, but a negative relationship between prejudice and negative stereotyping, and this relationship remained rather stable from early to late adolescence. Implications on the fight against prejudice towards immigrants amid early, middle, and late adolescents are also debated.