Two experiments compared incidental (implicit) and intentional (explicit) memory performance in adults with Asperger's syndrome and individually matched controls. Experiment 1 involved perceptual tests using word fragment cues, following study tasks in which the participants either generated the words from contextual cues or read the words alone, with no contextual cues. Experiment 2 involved conceptual tests using paired associate cues, following study tasks in which the paired associates were rated either for their relatedness or for their readability. Performance in both the incidental tests was similar for both groups. Performance in both the intentional tests was also similar for both groups, with one exception. The adults with Asperger's syndrome were more likely to falsely recall words that had not actually been studied. These findings further delimit the nature of memory impairments in adults with Asperger's syndrome, which seem restricted to certain aspects of episodic memory that include the tendency to make more intrusion errors in recall.