PURPOSE: This study was undertaken to correlate the CT and histopathologic findings of abscess wall. MATERIALS AND METHODS: The CT findings of 12 patients with pathologically proven brain abscess were retrospectively analyzed with particular attention to the thickness, smoothness and uniformity of enhancing abscess wall, and the results were correlated with histopathologic findings. RESULTS: Two patients with acute cerebritis showed an isodense ring on non-contrast CT(NCCT), but a true capsule formation could not be identified at pathologic examination. Six other patients with isodense ring on NCCT consisted of early to late cerebritis(3 cases), late cerebritis to early capsule(1 case), early capsule(1 case), and late capsule(1 case). These 6 cases showed ring enhancement on contrast enhanced CT(CECT) and true capsule formation pathologically. There was no isodense ring on NCCT in the remaining four patients. They consisted of early to late cerebritis(2 cases), late cerebritis(1 case), and late cerebritis to early capsule formation(1 case). These also showed ring enhancement on CECT and true capsule formation pathologically. CONCLUSION: We found that it is difficult to predict the exact stage of brain abscess on preoperative CT findings. It is suggested that clinical findings and sequential dynamic CT may provide more detailed informations for evaluation of abscess staging.