Applying a morphometric analysis, the effects of chronic alcohol consumption on Golgi-impregnated Purkinje cells from the rat cerebellar cortex were evaluated. Alcohol-fed animals received ethanol up to 1, 3, 6, 12 and 18 months and controls were given the same amount of food and an aqueous solution with sucrose replacing the ethanol isocalorifically. The following parameters of Purkinje cell dendritic trees were studied: dendritic field area, branching density, total branch length, spine density and total number of spines. Results showed a progressive decrease of all parameters in alcohol-fed animals. Significant differences were found in all rats after 12 months of alcohol intake. The reduction of the dendritic network was found to be related to a drop in mean total number of dendritic branches after 6 months of alcohol consumption. It is concluded that long-term alcohol consumption induces a decrease of the synaptic receptive area of Purkinje cells which may well lead to functional changes in the cerebellum.