Cow's milk anaphylaxis is the most common food-induced anaphylaxis in Iranian children. The clinical and laboratory findings of cow's milk anaphylaxis are evaluated in this study. All children who had experienced cow's milk anaphylaxis and had been referred to Immunology, asthma and allergy research center during a 5-year period were considered. After fulfilling a questionnaire, patients underwent measurement of total IgE and cow's milk-specific IgE by Immunocap test and Skin prick test (SPT) with cow's milk extract. Patients with a convincing history and one positive cow's milk-specific IgE test (SPT or Immunocap test) and patients with both positive tests were enrolled, in this study.Out of 49 patients, 59.2% were male. Patients' mean age was 5 years old and their mean age at the time of first attack was 5.7 months (SD = 4.3). Most of the patients have experienced more than one episode of anaphylaxis (79.5%) and in 85.7% of all cases, first attack occurred during the first year of life. Severity grading 1-5 were 2%, 6.1%, 18.4%, 69.4%, 4.1% respectively. Most common manifestations were cutaneous 98%, Respiratory 91.8%, Gastrointestinal 55.1%, Cardiovascular 46.9% and neurologic 46.9% signs and symptoms respectively. Twenty four patients showed positive SPT. Mean total IgE was 239.6±3.3 (IU/mL) and mean cow's milk-specific IgE was 19.28±27.2 (IU/mL). Most patients showed reactions only after ingestion of cow's milk or after dairy foods (81.6%).It is concluded that cow's milk anaphylaxis may happen early in life. Regarding the severity of attacks and remarkable number of patients with several attacks, poor knowledge about this disorder is evident.