The present study deals with the factors affecting the prognosis in the acute stage of 29 cases with hypertensive thalamic hemorrhage diagnosed by CT scan. It was thought that the following factors were significantly related to the outcome of the patients who were unable to lead daily life, remained in vegetative state or died: (1) consciousness level was below 10 in the so-called 3-3-9 formula, (2) bilateral Babinski's signs were observed, (3) localization of the hematoma was all the thalamic nuclei type, (4) hematoma volume was above 10 ml, (5) the maximum dimension of hematoma was over 30 or 35 mm, maximum width over 30 mm, maximum length over 25 mm and maximum height over 30 or 40 mm, and (6) the ventricles were dilatated. The prognosis had no significant relationship with the age of the patients, the side of the hematoma, the presence or the absence of ventricular penetration of the hematoma, or the existence of midline shift. We believe that in the acute stage of hypertensive thalamic hemorrhage, the prognosis can be forecasted by neurological findings, accurate calculation of the hematoma volume and size, localization of the hematoma and presence or absence of ventricular dilatation as determined by CT scan.