We compared clinical data from 45 patients with Huntington's Disease (HD) with CAG triplet repeats and the planimetric measurement of the caudate nucleus head area (CNHA) in CT scans. The mean age of patients was 50.4 yrs (SD +/- 10.2), the mean duration of HD 7.4 yrs (4.6), the mean age at the onset of HD 43.1 yrs (11.1). HD started with motor symptoms in 28 patients, with psychiatric symptoms in 14 patients, the history was unknown in 3 patients. The paternal transmission was observed in 29 patients, the maternal one in 12 patients, unknown in 4 patients. The mean number of CAG repeats was 46.6 (6.1). The mean CNHA was 0.4 cm2 (0.1). We found statistically significant reversed correlation between CAG repeats and the age at the onset of HD (p < 0.0001, r -0.6). The earlier onset of HD in patients with the paternal transmission compared to the maternal one was found statistically significant (p < 0.05). This phenomenon was not related to the larger number of CAG triplets in patients with the paternal transmission. No differences either of the age at the onset of HD or numbers of CAG repeats were found between subgroups of HD patients starting with motor or psychiatric symptoms. We also observed the significant reversed correlation between the duration of HD and CNHA measurement (p < 0.001, r -0.5). Even in the earliest stage of HD patients showed the marked atrophy of CNHA.