PURPOSE: To evaluate regional differences of 1H magnetic resonance(MR) spectral patterns in normal adulthuman brains. MATERIALS AND METHODS: A total of 44 1H MR spectra in 25 volunteers aged 27-45 were obtained infive regions including the frontal lobe(10), parietal lobe(10), temporal lobe(5), basal ganglia(10) and thalamus(9). 1H MR spectroscopy(MRS) was performed using a PRESS sequence with a TR of 2000ms and a TE of 270msfrom a volume of cm on a 1.5T clinical MR unit. Relative metabolite ratios of NAA/Cho, NAA/Cr and CR/Cho in eachregion were measured and compared. RESULTS: A total of 44 reliable spectra were successfully obtained in allregions. NAA/Cho, NAA/Cr and Cr/Cho ratios varied considerably, ranging from 1.09 ±0.2 to 2.46 ±0.25, from1.72 ±0.35 to 2.45 ±0.25 and from 0.64 ±0.1 to 1.01 ±0.12, respectively. Significant regional difference sin metabolite ratios were observed; higher NAA/Cho and NAA/Cr ratios in the parietal lobe, lower NAA/Cho ratios inthe temporal lobe, and lower Cr/Cho ratios in the temporal lobe compared to those of other regions(p<0.05). Differences in metabolite ratios between the right and left frontal lobes, and between the right and left basalganglias were not significant. CONCLUSION: 1H MR spectra of the normal adult human brains using in vivo singlevoxel 1H MRS represented significant regional differences in metabolite ratios of NAA/Cho, NAA/Cr and Cr/Cho. Our1H MR spectroscopic results are a useful ueference for assessing the 1H MRS pattern of various intracranial diseases.