Radiation exposure dose for patients during brain CT scan with General Electric C.T./T.8800 was measured using CaF. :Mn thermoluminescent dosimeter chips. The skin dose in single slice scan was 1.26±0.1 0 rad, and that in 9 slice scan was 2.06±0.16 rad. So the ratio was 1.63. The surface dose in profile along axial distance in multiple slice scan was also measured, and was found to be low at the junction of 2 slices. The lens dose in multiple slice scan was 0.27±0.05 rad , too small to induce any pathologic condition. As noted from the above data, the radiation exposure dose during CT scanning is not high compared with other radiologic examinations.