Previous studies concerned with the use of errorless learning (EL) in memory rehabilitation of patients with Alzheimer's disease (AD) combined EL with other techniques, such as expanded rehearsal, to facilitate learning. These studies focused on the re-learning of previously familiar information and did not investigate the learning of novel information. The aim of the present study was to investigate if EL provides a better training technique for AD patients than errorful learning (EF). For this purpose, learning of familiar material and learning of novel associations in four patients with probable AD was compared under EL and EF conditions. Combined data analysis demonstrated a significant advantage of EL over EF both for old and novel learning. However, patients also learned significantly in the EF condition and the EL effect was not large enough to reach significance on an individual level. It is suggested that EL may be most beneficial for patients with profound amnesia, and in situations that make effortful processing difficult, but that residual explicit memory capacities may override EL benefits.