Longitudinal studies are clearly needed to clarify the evolution of the neuropsychological profiles of Alzheimer's disease. The objective of this study was to investigate the longitudinal evolution of semantic memory deficits of AD patients. Fifty patients evaluated at the Memory Clinic of Hospital San Igancio in Bogotá–Colombia were included. Diagnosis was made by consensus (Geriatry, Neurology, Neuropsychology, Psychiatry), according to NINCDS–ADRDA criteria (McKhan et. al, 1984). At the first evaluation, all patients were in a moderate stage of the disease (GDS 3–4). Each patient had at least 4 longitudinal assessments, with a mean of 12 months between them. Classifications through K means–cluster analysis were made to determine the groups with high semantic deterioration (20 patients) and low semantic deterioration (20 patients), based on semantic verbal fluency and naming task results. A longitudinal design of repeated measures and multiple comparisons was established. In all evaluations, the group with high semantic deterioration was significantly (p< 0.05) more impaired in naming tasks, in proverbs and similarities. In semantic verbal fluency, only the first evaluation discriminated the two groups. In attention, memory and viso–constructional task, no differences were found between the groups in each evaluation. The analysis of the evolution of the disease demonstrates that the progressive nature of the disease is very heterogeneous and that not all cognitive functions have the same profile of impairment. The results are discussed in terms of the access and degradation theories of semantic memory.