Pneumoperitoneum during laparoscopy has been known to result in a rise in intracranial pressure (ICP) in experimental studies. There are no reports of the effect of pneumoperitoneum during diagnostic laparoscopy in patients suffering closed head injuries. We present the case of a 39 year old male with a closed head injury. Diagnostic laparoscopy was performed while intracranial pressure was monitored. ICP increased from 9 mmHg to over 60 mmHg within 10 min of pneumoperitoneum. Laparoscopy was terminated and the ICP returned to normal levels within 35 min. The authors recommend that pneumoperitoneum laparoscopy should not be used in the trauma setting where head injury is suspected.