Cognitive impairment is a frequent complication of stroke. The aim of this study was to evaluate the effectiveness of cognitive training performed early after stroke. Ninety-two patients were randomly assigned to either the study group (SG) or the control group (CG). Cognitive rehabilitation consisted of 16 individual one-hour sessions in which patients performed therapist- guided computer exercises. The patients in the CG performed a sham intervention. After four weeks all the patients were re-evaluated. In the SG, significant improvements (p<0.05) were detected in all neuropsychological measures at the post-training evaluation, while the CG showed mild (not statistically significant) improvements on cognitive tests. Between-group analysis revealed statistically significant differences in the domains of memory and visual attention. Cognitive training performed early after stroke seems to be a viable option for improving cognitive outcome in stroke survivors. Further studies should assess whether this may favor their reintegration into everyday life.