To estimate the surgical efficacy of decompressive craniotomy, 23 children under 2 years of age with acute shaken/impact baby syndrome were treated with medical or surgical methods over the past 6 years. Six children (group A) with lower intracranial pressure (ICP, less than 30 mm Hg) were treated with medical therapy, and 17 children with high ICP (more than 30 mm Hg) of which 7 children were treated with medical therapy (group B) and another 10 children (group C) were treated with decompressive craniotomy. Bifrontal craniotomy was performed on 5 children with generalized brain swelling. A large frontotemporoparietal craniotomy was performed on another 5 children with unilateral swelling. A mean of 32 ml of subdural hematoma was removed. The mean ICP was reduced by 80% in the craniotomy group, p < 0.05. Children in groups A and C performed better on the Children's Outcome Scale than those in group B, p < 0.05. Mortality was significantly lower (0/10) in group C than in group B (3/7), p < 0.05. Hearing preservation was better in group C than in group B, p < 0.05. Bifrontal and frontotemporoparietal craniotomies may reduce mortality and morbidity for acute shaken/impact baby syndrome with high ICP. Patients with ICP less than 30 mm Hg may be treated successfully with medical therapy and patients with ICP more than 30 mm Hg are better treated with decompressive craniotomy.