Purpose: To evaluate severity and built a pilot of a national databank about pediatric trauma and to determine its severity. Methods: Prospective study of unintentional pediatric trauma in five hospitals in the city of São Paulo, Brazil. Results: 916 patients in 4 months. 61.5% of traumatized children were male, average 6.5 years. 48. 4% were falls. Most families had an average monthly income less than three minimum wages. 42% of accidents occurred at home. 18.9% of children were alone. 59,8% of parents thought it could be prevented. 26.5% of children had previous accidents. GCS was severe: 5 patients, moderate: 8 patients. 21 patients were intubated (2.4%), RTS <7 in 10.2%, PTS<8 in 3.6%. 8.5% patients were considered severe, which was related to falls (p=0.001); sports (p=0.045); pedestrian (p=0.006); child education (p=0.015) and cared by male (p=0.007). Conclusions: Severity occurred in 8.5% and was associated to falls, sports, traffic, child education, and cared by male. Simple preventive measures could have prevented most of the accidents. The tested tool for details was successful and can be used throughout the country.