BACKGROUND In this study, we aimed to set levels of blood S100B and lactate and to determine any correlation with brain computerized tomography in minor head traumas in children and adults. METHODS This clinical trial is a prospective study including 100 head trauma patients who applied to Ankara Training and Research Hospital emergency service. RESULTS In this study, cut-off ranges of 0.0-0.15 ug/ml and 0.9-1.7 mmol/L for blood S100B and lactate levels, respectively, were used. S100B level was higher than the cut-off range in 42% of patients and lactate level was higher in 56% of patients. No significant differences were determined between age groups. When the relation between S100B and lactate levels with brain CT was evaluated, no statistically significant relation was determined. CONCLUSION According to our results, in minor head traumas, the determination of elevated serum S100B and lactate levels cannot take the place of clinical examination and the use of cranial CT. Although the patients in our study group had minor head trauma, we do not consider S100B and lactate to be reliable markers for estimating progression.