Background: Anaphylaxis is a severe, potentially fatal, systemic hypersensitivity reaction induced by various triggers. Objective: Only a few studies have examined the clinical manifestations of childhood anaphylaxis across different age groups. We aimed to evaluate, according to age group and trigger, the clinical features of anaphylaxis in pediatric patients. Methods: We retrospectively evaluated 130 children diagnosed with anaphylaxis over 11 years. Results: The median age of the patients was 10 years (min–max: 0.5–17.8), and 83 (63.8%) were male. Regarding age groups, 23 (17.7%) of the patients were infants, 26 (20%) were preschoolers, 31 (23.8%) were school-age children, and 50 (38.5%) were adolescents. Among the causes with known triggers, the most prevalent trigger was identified as food— affecting 44 (33.8%) cases—followed by drugs (34 cases, 26.2%) and venoms (18 cases, 13.8%). There was a statistically significant relationship between age groups and triggers (p < 0.001). The triggering role of drugs and venoms was found to be low in infants. Also, the infant group had significantly lower risks of venom-induced and drug-induced anaphylaxis compared to the adolescent group. The top three triggers identified in our patients were compared according to the system involved, and a statistically significant relationship was found between triggers and cardiovascular findings (p = 0.006). Conclusion: The etiology of anaphylaxis may vary by age group. Depending on the trigger, it may also have different clinical manifestations.