This is a description of a computerized tomographic study of 45 non-delusional depressed, 29 delusional depressed patients and 77 neurotic control subjects. The cerebral atrophy ratio (CAR) on the three different slices and the ventricular ratio (VBR) of the anterior horn and the body of the lateral ventricles were calculated, analyzed and compared using Student's t test. Compared to the control subjects, the non-delusional depressive patients had greater CAR values than the controls but there were no significant differences of VBR values between the two groups. The patients with delusional depression had significantly larger CAR and VBR values than the non-delusional depressives and control subjects. The delusional depressives had greater brain atrophy than the non-delusionals and it was suggested that organic cerebral factors may have etiological significance in the depressions, especially the delusional depressives.