Background No information exists on how the knowledge or the practice of pediatricians regarding anaphylaxis episodes vary with episode severity. The aim of this study was to assess and compare pediatrician knowledge on the management of mild and severe anaphylaxis using clinical scenarios and to determine factors that affect their decisions. Methods A questionnaire consisting of eight questions on the diagnosis and management of anaphylaxis was distributed at two national congresses. A uniform answer box including possible response choices was given below each question, and respondents were asked to check the answers that they thought appropriate. The management of mild and severe anaphylaxis was examined using two clinical case scenarios involving initial treatment, monitoring, and discharge recommendations. Results Four hundred and ten questionnaires were analyzed. The percentage of pediatricians who correctly answered all questions on the management of mild and severe anaphylaxis scenarios was 11.3% and 3.2%, respectively. Pediatricians did significantly better with initial treatment, but they were less knowledgeable with respect to observation time and discharge criteria in the mild anaphylaxis case scenario compared with the severe one (both P < 0.001). Multiple logistic regression analysis identified only working in an emergency department or intensive care unit as significantly predicting correct diagnosis of anaphylaxis among pediatricians (P = 0.01, 95% confidence interval: 0.11-0.57). No pediatrician-related factors predicted physician knowledge on the management of anaphylaxis. Conclusions Pediatricians have difficulty with different steps in managing mild and severe anaphylaxis. Their deficiencies in management may result in failure to prevent recurrences of mild anaphylaxis and may increase mortality in severe anaphylaxis.